Well... you already can see the boot up screens for Sega CD. You can't turn it on or off as far as I know, but now I know what you're asking.
I don't know.... Madmab...? Is this something that wouldn't be too much of a pain to add? It does seem like it would be pretty cool, especially if you could turn it on/off if you didn't want to see it.
I wouldn't wait on Madmab to see if he could do the X-Men thing though. I could be wrong, but I think it would be a moderately difficult thing that would eat up a lot of his coding time. I don't think he'd have too much personal interest in it himself, and I'm pulling for him to get sort/filter support and alternate favorites working now. His coding time is limited because he's got a hell of a lot more of a personal life than I've got currently
I would be very interested if you could recruit anyone with coding experience here, particularly XBox coding experience. There are plenty of dummies like me on the scene that can do the grunt work (actually, that's a lie because I wish we had at least 10 more Mega Man ?'s, Stupot1's, Horscht's and pCeSlAyEr's), but I'd like to see a few more people with the ability to help code things work with madmab. XT did an amazing thing and got Paperboy II, Best of the Best, Crime Busters, some Mario hacks and a few other games working on NES and Madmab should be compiling those soon. He's also working on getting support for Great Wall (and I hope a few more Pirates that need mapper support).
I would LOVE to see a few more people here who could do a little niche work like that and work with madmab to get it all compiled in the new betas.
Let me know man. I'm seriously interested in this. If it's possible, this is some of the best news I've heard in a while.
Later,
~Rx