Without a doubt the fastest bike I rode all day. The Intense Spider 29 may be nothing short of the perfect cross country race bike (unfortunately Intense's site is built entirely out of Flash so I can't link to the details for you).
I felt absolutely no pedal bob. The Virtual Pivot Point (VPP) rear suspension design was flawless...very tight, yet active. The bike turns on a dime and tracks with the best of them. The Spider 29 is sold as a frame only so it can be built up just the way you like.
Not quite as plush as the Niner R.I.P. 9, but faster. For all day epics pick the Niner, for speed and general cross country riding the Spider 29 is your ride.
Still have a few more full suspension 29ers to test so we'll see if this remains the reigning champ.