How to: Gaming Video Creation and Export (for youtube)
Get Mediacoder: http://www.mediacoderhq.com/download.htm
The video basically shows how to set up the document settings (and framerate) correctly, then how to export it uncompressed, how to set up the media coder settings correctly and how to encode.
If possible: always render to a different harddisk than your source files are located. It will speed up the process around x2. Especially when working with uncompressed video it's much slower when the PC has to read and write on the same HD at once with full speed.
It is always nice to use higher bit rates, but don't go under 3000 Kbit/s for 720p HD videos and not under 5000 Kbit/s for 1080p HD videos. For audio don't go below 160 Kbit/s. Don't use B-Frames, they can cause problems when youtube is transcoding your video.
You can also export multiple videos at once making multiple selections with markers and then by using the batch renderer script. You just have to make sure that the export settings are saved and not set back to 29.97 fps. While Sony Vegas is exporting the used fps and video resolution are displayed above the time line. If it's set wrong you can easily stop the script. Anyway, I think it's easier to just make a single selection and then export on the regular way.
Mediacoder allows multiple video exports at once, just drag and drop all videos into the window.