For the first time Microsoft shared publicly its Windows 7 vision and development progress at the Professional Developer Conference in Los Angeles. So far Windows 7 is shaping up to be a very interesting release. The dev team is already way past the Milestone 3 build 6801 released to PDC attendees. Build 6933 was shown at the keynote and included a lot of interface changes including the new Taskbar and other refinements. For still being a pre-beta build, 6933 looks and feels more like a Windows Vista release candidate.

One of the reasons for increased reliability and speed can be attributed to the new Windows development process but it can also be attributed to the renewed effort to focus on improving the foundation of the OS. Unlike Windows Vista, Microsoft is making major commitments to improving Windows fundamentals. There is a lot going on with Windows 7 under the updated GUI so let’s get into the details:

Faster and More Responsive

• Microsoft is working to make Windows 7 much faster at startup and shutdown. In fact, pre-beta builds already start and shut down faster than Windows Vista. However, more work is needed to get to the 15 second boot goal but they are getting close. Standby has also been improved. When resuming from standby Windows 7 is ready in seconds and any previous wireless network connections are automatically reconnected.
• Internet Explorer 8 starts faster and has an improved JavaScript engine that performs much better. JavaScript intensive web sites are becoming a common occurrence in the Web 2.0 world and IE8 needs to execute JavaScript well to remain competitive with FireFox and Chrome.
• Search in Windows 7 has been improved and includes performance enhancements from Windows Search 4.0. Sorting and Grouping of search results are also much faster.
• ReadyBoost that first appeared in Windows Vista has been enhanced in Windows 7 to support using multiple flash devices at once. Now users can go crazy sticking usb keys in every available usb slot.
  
• Windows 7 uses trigger-started services for many system services so they are only started when they are needed. For example, the Bluetooth service only is started when a user connects a Bluetooth device to the system.
• The size of the Desktop Windows Manager (DWM) and the graphics stack were reduced to improve performance on lower end graphics hardware.
• There have not been many changes in the Windows 7 kernel but there have been a number of Optimizations.  One optimization to the Dispatcher Lock mechanism greatly improves Window's performance on multi-core systems. In fact, Windows 7 can now support up to 256 cores on a single system.
  

Reliability

• A new fault tolerant system heap was redesigned to automatically resolve common memory mismanagement issues so offending applications will not crash. Microsoft says that about 15% of application crashes today are because of heap corruptions.
• Process Reflection reduces the disruption caused by diagnostics when an application crashes. Instead of making you wait before re-launching the application Windows will clone the failed process and analyze it in the background.
• Reliability Monitoring has been improved with a new user interface and better, more detailed, data collection.
• New printer driver sandboxing prevents poorly-written printer device drivers from affecting the entire system. If a driver or printer hardware causes a crash then the damage will be isolated to just that device instead of taking down the entire system or other hardware devices.

Improved Battery Life

• The simplest way to increase battery life is to reduce the load on the processor. If a processor is idle then it uses less power increasing battery life. Windows 7 increases the amount of time a processor is idle by reducing background activities and also using trigger started processes that I mentioned earlier.
• Adaptive display brightness has finally made its way to Windows 7. Much like a cell phone, when the device is not in use the screen brightness will dim to save battery life. However, Windows 7 adaptive display brightness is more intelligent. If the screen is set to dim at 30 seconds and you immediately move the mouse or hit a key to brighten the display Windows 7 will automatically increase the interval before it dims the display again.
• DVD playback is improved in Windows 7 to use less processing power and also manage more efficiently when it spins the DVD to reduce power consumption.
• Wake on Wireless LAN is a new feature that finally allows users to let their laptop go on standby but still access it from the network without having to manually turn it back on. This would allow you to leave your laptop on standby in your office and if you wanted to access a file on it over the wireless network it would automatically be woken up so the file can be accessed. This was previously only available when using a wired connection with Windows.
• Smart network is my favorite “common sense” feature to improve battery life on any laptop and its now in Windows. Windows 7 will automatically turn off your wired network adapter when it’s not in use. What a great way to save power when you are using your wireless network connection.

Application Compatibility

• Microsoft has made it very clear they are not going to make the same mistake with Windows 7 they made with Windows Vista app compatibility. They have promised that if an application is compatible with Windows Vista it will work with Windows 7.
• New compatibility tools and processes have been created for internal developers to ensure application compatibility.
• Windows 7 also includes in-box compatibility aids that automatically fix broken applications. For example, if an application install fails because it does not like the Windows 7 version number the compatibility aids can automatically patch the install with the help of a database of application shims to successfully run the install.

Device Compatibility

• Microsoft did not change the device driver framework in Windows 7 so Windows Vista device drivers should work properly in Windows 7.
• To make sure that older hardware works with Windows 7 Microsoft is improving Windows Update to include even more third-party driver that can be downloaded and installed automatically after Windows 7 is installed.

Improved Security

• User Account Control (UAC) is probably the most popular feature of Windows Vista because of the frequent security prompts. While the feature reduced malware infections in Windows by more than 60% compared to Windows XP it also was the most annoying feature in Windows Vista. UAC will remain in Windows 7 because it has proven to be a reliable security device to prevent infections but uses will see it far less often. Additionally, Windows 7 includes a new UAC control panel that allows the user to select how many security prompts they want to see. Users now have 4 levels of UAC security that vary from no prompts at all to a prompt for every change to Windows. 
• Windows Defender has a streamlined user interface within the consolidated Windows 7 Action Center. Most importantly, the performance of real-time protection was optimized to reduce impact on system performance.
• Windows Filtering Platform provides an official and safe way for security vendors to tap into Windows to offer additional or replacement security software. No more hacking the kernel to tap into Windows.
  

With the buzz surrounding Windows 7’s new user interface it is easy to overlook the changes behind what users can see. But as you can now see, there is a significant amount of changes under-the-hood that make a big impact in Windows 7.