I agree about it's awesomeness! I'm triple booting Ubuntu 9.10, Linux Mint, and Windows 7. I use Windows and Linux each about 50% of the time, and I appreciate the nuances of both. I'm comfortable using a terminal to do command line operations, and I don't mind a dos prompt either.
I tend to find that both operating systems offer ease of use in areas that the other doesn't. Using both has absolutely increased my productivity over using either. I've been 100% linux before, and 100% windows before, and working with both has just made things better for me.
Whenever my friends have computer issues, they come to me. I almost always take the opportunity to introduce them to Ubuntu, and so far 100% of the time, they are way happier with it than they were with XP or Vista when it comes to basic/intermediate tasks. Anything advanced like Adobe Creative Suite, Final Cut Pro, etc are better for Windows/Mac. Anything advanced and technical like wifi hacking Linux still wins.
In summary, I love being a multi-OS user, and Ubuntu gets a TON of play from me. I'm pumped about 10.04.