Short story is keep Windows 7 for your desktop and laptop but don't count out Windows 8 for your tablet, because it has the potential to be pretty good for tablet use (READ: TOUCH FRIENDLY).
Long story:
When I first installed it and ran through the initial startup I noticed right away that simple was the name of the game for Windows 8, with a plain background and a few questions and your off. Right away your greeted with the Metro sexual a mean Metro interface.... Not so bad at first look but when you need to get to it from the desktop (it replaces the start menu) you might be a bit lost at first and frustrated because it took me about 5 to 10 minutes to realize how to get to it from the desktop! You have to mouse over to the very bottom left corner of the screen (I mean the very last few pixels of the corner of the screen) and click on it but the thing is its blank, just a blank piece of the task bar from where the start orb SHOULD be. So how I'm I supposed to do that on a regular basis? They should have just kept the start orb and let that be the thing you click to get to the Metro interface.... If anybody is familiar with the Ubuntu Unity bar than this should sound similar, If mouse over to the very bottom right corner of the screen a little dock shows up on the right side of the screen with buttons for settings, start (Metro), search, and something else I can't remember at the moment.It's pretty useless and ends up feeling tacked on just like the rest of Metro. The only thing I found it useful for is easier access to settings but it ends up being a necessity while in Metro as it's needed to access settings for Metro and other things. Overall they should have left that in Metro only. Another thing that took me awhile to find was the control panel, you have to go through the Metro/side dock to get it! Bad thing is the control panel is the same as in Windows 7 for the most part but where is the bad part you say? Well to change settings for Metro you must go through the Metro interface to do it making you juggle between two interfaces and settings. That is exactly what Windows 8 feels like, a juggle between two different interfaces that don't seem to play nice together. However there still is good to be found for power users. For those that like (including me) ribbon has made a comeback! but into Windows Explorer this time which provides a lot of options, configurations, and the like. In addition to this, the task manager has gotten an overhaul, adding much more functionality to it and ease of use. We may still be in the Beta phase but for power users and just desktops/laptop users in general, you should stay away because this OS seems much more oriented to touch based mobile devices and to think that if Microsoft would have actually integrated Metro instead of tacking it on, Windows 8 would be much better. All in all, there is not much incentive to upgrade especially considering that Windows 8 is still based on the Windows NT 6.x kernal just like Vista and 7 (6.2 for Windows 8, 6.1 for 7, and 6.0 for Vista) meaning most programs should compatible between the three OS'. They probably well even have DirectX 11.1 for Windows 7 and maybe even Vista.
But you know, you don't have to take my word for it so I just recommend you try it while you can (VirtualBox anybody?).
Long story:
When I first installed it and ran through the initial startup I noticed right away that simple was the name of the game for Windows 8, with a plain background and a few questions and your off. Right away your greeted with the Metro sexual a mean Metro interface.... Not so bad at first look but when you need to get to it from the desktop (it replaces the start menu) you might be a bit lost at first and frustrated because it took me about 5 to 10 minutes to realize how to get to it from the desktop! You have to mouse over to the very bottom left corner of the screen (I mean the very last few pixels of the corner of the screen) and click on it but the thing is its blank, just a blank piece of the task bar from where the start orb SHOULD be. So how I'm I supposed to do that on a regular basis? They should have just kept the start orb and let that be the thing you click to get to the Metro interface.... If anybody is familiar with the Ubuntu Unity bar than this should sound similar, If mouse over to the very bottom right corner of the screen a little dock shows up on the right side of the screen with buttons for settings, start (Metro), search, and something else I can't remember at the moment.It's pretty useless and ends up feeling tacked on just like the rest of Metro. The only thing I found it useful for is easier access to settings but it ends up being a necessity while in Metro as it's needed to access settings for Metro and other things. Overall they should have left that in Metro only. Another thing that took me awhile to find was the control panel, you have to go through the Metro/side dock to get it! Bad thing is the control panel is the same as in Windows 7 for the most part but where is the bad part you say? Well to change settings for Metro you must go through the Metro interface to do it making you juggle between two interfaces and settings. That is exactly what Windows 8 feels like, a juggle between two different interfaces that don't seem to play nice together. However there still is good to be found for power users. For those that like (including me) ribbon has made a comeback! but into Windows Explorer this time which provides a lot of options, configurations, and the like. In addition to this, the task manager has gotten an overhaul, adding much more functionality to it and ease of use. We may still be in the Beta phase but for power users and just desktops/laptop users in general, you should stay away because this OS seems much more oriented to touch based mobile devices and to think that if Microsoft would have actually integrated Metro instead of tacking it on, Windows 8 would be much better. All in all, there is not much incentive to upgrade especially considering that Windows 8 is still based on the Windows NT 6.x kernal just like Vista and 7 (6.2 for Windows 8, 6.1 for 7, and 6.0 for Vista) meaning most programs should compatible between the three OS'. They probably well even have DirectX 11.1 for Windows 7 and maybe even Vista.
But you know, you don't have to take my word for it so I just recommend you try it while you can (VirtualBox anybody?).