I've just rendered a Cineform intermediary out of Vegas 8. Good job it was a short project because the result is pretty nasty-looking:
All those bands and coloured blocks move according to frame content. This is with a clip rendered out of Vegas from an HDV m2t timeline, I don't have Neo. The same clip viewed back in Vegas looks just the same, as is the case in Virtualdub.
Any ideas? I'm having to resort to HUFFYUV.