Good news, the folks at Revision are working on Vegas plugin for the super slow mo FX due by mid Summer this year!

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Cool video by Johnni Behiri

Very nice. Definately keep an eye on this plug ins.

It would be totally awesome to have twixtor wrapped with Vegas!!!!

where did you hear this!!!

Or will it be plug-in or a standalone

It might not be an official support, but you can already use the OpenFX version on twixtor within Vegas 10.

http://www.dvinfo.net/forum/what-happens-vegas/490473-anyone-tried-twixtor-vegas-pro-10-a.html