Would anyone be able to explain this? I would love to know why it did work. It just makes no sense to me that if it worked even though it's not supported, that it doesnt a few days later...
Is CoreAVC working for VC1? What are my options?
CoreAVC does not
support VC-1. Period.
Also, define "worked". VC-1 can never have streamed to your PS3, natively, inside an m2ts file. Simply impossible. If by "worked" you mean: "didn't stutter", or some such, then there can be any myriad of reasons for that. Most notably, and likely, your quality-settings have changed in-between.
Also, the guy with the C2D E6300 can forget about real-time transcoding of VC-1 (in any half-way decent quality, at least). On my 3.2Ghz Q6700 I can only just get full-screen 1080p VC-1 to transcode properly (at highest quality) when I disable the wmv9 codec in ffdshow, and set it to libavcodec. Now, the latter is slightly faster; also, slightly buggier, and doesn't do interlaced VC-1 material yet. As for libavcodec's bugginess, that's relative: if you're doing an x264 reencoding of VC-1 stuff that will take days, then even 1 glitch is 1 too many, as you'd have to start all over again. For real-time transcoding, however, who cares if you run into a very rare bug now and then? So, just set ffdshow to use libavcodec for VC-1, for that extra bit of speed.