Welp with Vegas Studio and Cineform I had gotten down to a recipe for a 720 MP4 rendor for Vimeo and YouTube. Had preset saved. It looked something like this:
Video:
square pixel
720 Video Internet HD
Sony AVC
Toler template
Video format: AVC
(Custom Frame size)
1280x720
allow source to adjust frame size
Profile:Main
Entropy coding: CAVLC
Frame rate: 29.970 (NTSC)
allow source to adjust frame rate
Field Order: None (progressive)
Bit rate (bps): 5,000,000

Audio:
Format: AAC
Sample rate (Hz): 44,100
bit rate (bps): 320,000

Now with Vegas Pro 10e there are a few different options that I just don't understand well enough to choose one over the other.
I've also processing the MOVs directly (rather than converting to Cineform AVI prior to editing and FX).
Lately I've gone ahead and and not produced the 720 downsize but just leave it at 1080p to render out to a MP4 - that way I can always burn a bluray disc too and don't the YouTube and Vimeo convert into their various sizes anyway?
Saw some YouTube hits which I'll have to check out tonight but if there are any links you would recommend for good baseline render settings I'd love to see them.

welp after starting a render last night it's still rendering this morning. It's a 9 and half minute combined two camera edit with two fxs. It's rendering to MP4 at full 1080p at a rate of 1 minute of video every two hours. Is my computer slow or my settings screwed up or both?