I saw a comment from Lauren Shuler Donner today that she'd be glad to work out an Avengers/X-Men screen crossover, but even aside from the legal/financial difficulties, I'm not sure how it would work, since the X-franchise these days seems to be set squarely in the past, and it's hard to see how to move forward from the present of The Last Stand.
Simple.. either completely ignore the abomination that was Last Stand or just go past it and take the very few things with you that were ok (Hank McCoy for example).
If the ABC SHIELD series is a hit then I think the best way that the other studios who own Marvel rights could then 'link up' would be to use the series as 'promotion' for their movies. Somet type of storyline or appearance from main/minor/villain characters in the show right around the time the movie is coming out.
Please god no! The last thing i want is for any show to become a marketing vehicle for any product.. i hate that with a passion.
I don't have a problem with commercial products appearing onscreen but they way it's done is to shove our nose in it.. these extended 2-3 seconds where the camera lingers on the product and its logo makes me want to hurl ( i nearly walked out of a Brosnan Bond once because it became so unbearable on the nose).