I just installed Ubuntu 64 bit on my AMD dual core this past weekend, and I like how it can be completely configured to what you want. I did manage to get Flash working, although I can't scroll the timebar on YouTube videos. They play at least.
I also can't get DVD's to play, plus I'm stuck with only 3 buttons on my mouse and can't use any others.
But I am liking it. It reminds me of the 'ol Amiga, and with Firefox I'll be using this to surf the internet to research. I got sick and tired of all the adware/spyware being tossed into my Windows XP system. So now, I keep XP Pro for my games and programs, and I use Ubuntu for surfing and fun.
I'd like to try Beryl, but I've read it's not very stable with 64bit and I'd hate to mess stuff up.
I did install Thunderbird, which works well. And I also put that "Kill App" on the bottom tool bar. I found that to be very useful.
What are some other great apps and games to put on Ubuntu 64? I dedicated 20 gigs to it, so I have some room to play around. I was hoping to get DoxBox working on it and perhaps some other emulators. I know they won't work as well as on XP, but it'll be neat to have on Ubuntu. I'm just glad that I have a safe way to browse the internet now. Even if I do get viruses/adware, it won't cross over into my Windows NTFS partitions because those are write protected from Ubuntu's side. I have to physically turn on the "write ability" in order to copy something over there.