First, I would like to point everyone to my favorite source for everything Windows, Paul Thurrott's Supersite for Windows. Paul has great knowledge about Windows and has an exhaustive list of screenshots and information about Windows 7 which can be found here .
Here are some of my own personal impressions about Windows:
1. The New Taskbar
The taskbar is one of the first and most obvious things that has changed in Windows 7. By default the taskbar is strictly "iconized" as I like to call it, meaning that all you see is icons.
As one can see even when applications are in the start menu, there is no text beside the icon. This can be changed through the settings to revert back to the "normal" windows behavior (which is what I did).
One might notice the icons that remain on the taskbar, despite not being opened in windows. These icons are now "pinned" to the taskbar. This pinning of icons replaces the previous Quick Launch feature in XP and Vista.
Another feature of the new taskbar is the small, closeable, live window previews that are accompanied by the icons. For example, if multiple Firefox windows are opened, it will look like this in the taskbar when you hover over the icon.
2. The addition of Libraries as opposed to strict folders.
One of my favorite features of Windows 7 is the addition of Libraries (a bit ironic I know). Libraries are separated in a similar format to the My Documents, My Videos, My Pictures, and My Music folders of XP, except they are not just limited to a single folder. Instead, the Libraries allow you to add as many folders as you like to them and keep your documents, music, photos, and videos in one place, even if they are physically located in separate folders. This is especially intuitive with regards to networking, as networked folders can be added to these Libraries.
3. The New Start Menu
Those who have used Vista will recognize the improved start menu in Windows 7. The search function is still built right into the menu box and only one major change is noticeable, which is the new hover options available to users.
When hovering over a program that works with this feature (Office products, IE, Sticky Notes, etc...), a mini-list of options will appear to the user. See above screenshot.
4. One-click Wireless Networking
Another favorite feature of mine on Windows 7 is the one-click wireless networking. By simply clicking on the wireless network icon in the system tray, you can instantly connect to any network that your wireless connection sees. This is a small but helpful feature.
5. No more Windows Movie Maker, Outlook Express, Windows Messenger.
One of the most interesting things that Microsoft has done with Windows 7 is removing some of the formerly key applications. Instead, Microsoft is going to require that you download the Windows Live Essentials Pack. In the Windows Live Essentials Pack, you will be asked if you would like to install programs like:
Windows Live Movie Maker (Replacing Movie Maker),
Windows Live Writer (a blogging program),
Windows Live Mail (Replacing the clunky and unintuitive Outlook Express,
Windows Live Photo Gallery (Replacing Windows Photo Gallery in Vista)
Windows Live Messenger (Replacing Windows Messenger)
These programs are immensely better then the previous offerings by Microsoft, and the the best part is that they are free and available now to XP, Vista, and Windows 7 users.
Some other changes to notable Windows programs include the revamped user interface of Microsoft Paint and Microsoft Wordpad, which now include the Ribbon interface made popular by Office 2007.
6. Overall Feel
The overall feel of the operating system is much snappier then both Vista and XP, assuming you have the hardware to run it. I'm currently using a laptop with 4 gb of RAM and a dual-core processor, so I'm running it without any problems. I've read that people trying to run it on slower machines are still running into difficulties.
Overall though, the system boots up faster, shuts down faster, and is generally very quick to respond.
Some Notes: I have merely touched on the new features of Windows 7. I encourage you to check out Paul Thurrott's site for more details. Also, while Windows 7 has been a great experience for me personally, it is still in beta. Beta means that Microsoft still has some bugs to squash and some errors to correct. I have only run into some minor errors every once in awhile, but I still do not recommend that users completely switch to Windows 7 without previously doing a backup of all of their files.
I'll end this post with a full screenshot of my Windows 7 desktop with the default wallpaper. Be sure to click on it for a full-size picture.
If you have any specific questions about the operating system feel free to comment, and I will try to answer as best I can.