It's happening and I can't help it.
I've always been happy with my 3.6" rear travel cross country bike, and believed that was all I needed. This last weekend, however, I was able to trade bikes with my friend for the day, and ended up questioning my cross-country purist ideals.
The bike I was riding was a Specialized Enduro Pro. I was very surprised that with the extra weight it actually wasn't really much harder to climb with, until we got to the super steep uphill. The downhill, though, just floated like fighter pods through the ewok forest. One thing I did miss was that I wasn't able to fly off of little bumps like I usually do on my cross country rig. Instead, any little or medium size bump just sort of dissapeared as I floated over them. But this allowed for a much faster speed going downhill, which is a good thing. Also a good thing is that the bike just flew off of larger bumps and landed softly and in control every time.
I have no way of pulling off a new bike purchase, as my girlfriend would flip her lid. Maybe someday my frame will break and I'll just have to get another frame... Until then I'll just live my big-hit life vicariously through the stories and posts of DBD, A2, Mael, BHM, and all you others that get to go bigger than me...