2007 will be the Year of the Lightweight, for a number of reasons:
1. There isn't a single fighter in either organization who rules his division the way Hendo, Fedor, and Chuck do (and as GSP and Cro Cop soon will).
2. The UFC's 155 division in particular is very up-in-the-air, because it's so new. It's going to be fun watching all those guys play "Kill of the Hill" this year.
3. There are some good, young fighters on the up. Joe Stevenson, Melvin Guillard, Gilbert Melendez, Tyson Griffin, Shinya Aoki, Bart Palaszewski, and Chris Horodecki.
4. Pride's Lightweight Grand Prix is coming, and those always seem to make for some fun fights. There's also a non-zero chance that this will be Pride's last grand prix.
5. The UFC's The Ultimate Fighter 5 will feature 16 lightweights, most of whom I've never heard of.