What kind of SWF support are you guys looking at? Is it just "Export to SWF" or do you want to import SWF files just like any other video and do edits on that?
Uhmm i do loads of flash video.
the best method is not to use the NLE to create that.... so IMHO even if SWF output was available in Vegas i would not use it.
Instead craft a properly sized unconstrained Sorenson 3 rendering
and put that thru Sorenson Squeeze to create a properly 2 pass VBR compressed video file in FLV format.
The FLV format created will be far more compact and memory efficient.
Then take that FLV format into your FLASH MX - manipulate your player code in flash - edit and publish from there.
I also have Wildform flix , but honestly Flash MX fed with a Sorenson Squeeze Pro compression to FLV format always gets the best outcome.
I mod at were-here.com ( forum for flash professionals ) - look for the DV forum.
True, NLE outputting to Flash is not desirable (flash is not the optimal format for general purpose video)... but may be with the new support for video in FlashMX, this could be of use.