Will - The D3x is great, but not for $8k. A brand new 21MP 1Ds Mark III is selling for $6,600 at B&H. I've been shooting Canon for the last 2 years, but still have a few Nikkors and SB800 speedlights laying around, hence my look at the D700. I need to keep balance between quality images and files that are too big for my current workflow and computers.
The 5D2 looks great, although the biggest disappointment (to me anyway) is that they did not upgrade the autofocus mechanism. The 5D2 is actually shipping - a fellow local photographer got her's this week. I'm going to play with it sometime next week hopefully.
As for whether to get the -24-105IS kit lens or not. What other lenses do you have? The 24-105IS is a decent lens and the IS works very well. I'm sure it will come in handy when working with videos as well as stills.
Speaking of videos, I came across some posted 5D2 videos on the interweb.
This one was produced with the 5D by Amy Wilson and David Stephenson of the Lexington Herald-Leader: http://www.davidstephenson.com/rocky_906.mov
This one from ArialPan
has some clips of the 5D on an Aerial Cam rig: http://www.youtube.com/watch?v=JVOqmbOdN0E