[Nick Gipson]"I exported my recent project in Vegas to it and I get this damn "This Project contains a sequence that could not be opened". error"
Did you get any errors or warnings when exporting from Vegas that some features would not be transferred? Converting between NLE's is not perfect and you will loose information guaranteed because Vegas can do things that Premiere cannot. Generated media is one area that won't translate over.
Personally, I would never switch NLE's in the middle of a project unless something was keeping you from finishing the project. Otherwise I would finish my Vegas projects in Vegas and start my new projects in Premiere. This is what I did with Final Cut Pro X. Even though Vegas can export of FCP X it wasn't' perfect and wasn't worth the trouble.