George Martin was awesome very important to the Beatles sound and everything! He was definitely a genius producer and anyone else *coughphilspectorcough* would not have suited them as well.
(goes and reads the original post)
OHHHHHHHHHHHHH! George Harrison doesn't need an appreciation thread. That guy is clearly awesome and towards the end of the Beatles he was on equal footing with John and Paul. No person in their right mind would think that George wasn't extremely important to the group. Also, many people feel that he has the best solo album out of all of them in All Things Must Pass. I am one of those people.
If you take George's songs off of Revolver or the White Album you are left with albums that wouldn't even be half as good...no a quarter as good.