I'm currently broadcasting live from the new Ubuntu 10.10. Here's a quick review of this new version:

1- EXTREMELY fast, light, very responsive, easy to use Version.
2- As for the interface, Ubuntu is doing a great job so far...
3- Booting the 10.10 version takes about 3 seconds only :) ... I restarted my system 3 times in ONE minute! (This is funny and everyone should try it :)
4- Plenty of new features are added. More software too.

That's it for now. Will be posting later on some additional features.
I absolutely love the 10.10 :) ubuntu never seizes to amaze me, its the time of the season when i have a rush towards open-sorcery :P
Review #2: Do not install Ubuntu at all. Period!

Okay, here's what happened:

After the successful install of Ubuntu 10.10, i started downloading some important programs and stuff i need.
At the next reboot, Windows & Ubuntu didn't load at all. A black screen with the following message appeared:
error: unknown filesystem
grub rescue >
What happened is that GRUB took control of the booting process, and when it fails to start, all the booting process fails too.

And like any other person, i googled this error message using another PC. and couldn't find any correct answer (or at least, none of them worked for me).

I checked SuperUser.com for an answer and i found one.
Luckily, I previously created a Windows 7 Rescue Disc before installing Ubuntu 10.10, so, i had to reboot the system from the Rescue Disc and enter the "Repair Windows" Mode.

After that, make sure you select the recovery prompt and type these commands one-by-one:
bootrec.exe /FixMbr
bootrec.exe /FixBoot

After you have done this, close the prompt with the X, and close the Windows 7 installer.
Reboot, and there you go... Windows 7 will load again.

I'm currently back to Windows 7, deleted all the Ubuntu partitions created. And for the moment, i'm not willing to go back and use Ubuntu !
i dual booted ubuntu and 7 with no problem at all :) Ayman had this problem as well. Im starting to think that the problem is hardware related....
Sometimes, the automatic configuration during setup will not correctly detect your partition scheme, it will write a flawed configuration file and that will cause boot problems.

It's not a grub-specific problem, I have screwed up multitudinous GNU/Linux installations, so I know that this can happen with both grub and lilo.

It's also not an Ubuntu-specific issue, have you ever tried installing Windows 7 and Windows Vista side by side? It takes a little messing around to get things the way you want them :)

That's why I perform all the Ubuntu installations for my friends, that way I can be sure that the system is working just fine and they'll have a nice experience!
probably you just gotta partition it right, but for me, I downloaded the iso 4 times and it was corrupted each time!

so check your iso if it is downloaded properly or not! As for ubuntu, its so awesome, but my problem with it is gaming... I cant switch over and leave WOW and StarCraft2...
Also am having trouble getting it to work with our company's exchange server and that sux since u really can't replace outlook

other than that the system is awesome :D I really recommend it for netbooks and light internet usage