opensuse 11.0, I know its not been released, but it will bring linux to the level of mac os x leopard.
Some people at distrowatch.com, I think some of the linux specialists have called it the most advnaced linux os ever.
OpenSUSE 11.0, one of the most technologically advanced distribution releases the Linux world has ever seen (Ladislav of DistroWatch) (And the most beautiful OS you have ever seen, I might add).
What about u linux ubuntu geek, whats your favorite OS? :)
You can't ever expect a bsd user to think of linux as the best cause technically bsd is superior to linux.
I know Solaris is as close as u can get to unix but lets face it, its GUI and hardware support sucks horribly and I am never going to use it anyway.
After opensuse 11.0, my favorite is Mac OS X leopard, then Tiger, then opensuse 10.3 and then to some extent windows vista.
Edit:
I never really like windows 98, though it was ok for its time.
I remember if I had a few apps open then something froze and the blue screen would appear and force u to reboot, I hated that. I actually like windows's operating systems using the nt kernel like windows 2000 pro, now that was stable, xp and vista r not as stable as 2000 but they r alright as well.