Yes. I know for a fact there is.
Of the big players, who?
I'm not trying to be snarky, I'm just curious who you are referring to and on what grounds (because I try to stay on top of these things). I suppose Paizo and Green Ronin might since both were clear in rejecting that version of the GSL but leaving open the possibility of supporting a new one.
However, even though Paizo has mentioned on their boards they might explore some 4e options, they have also been very clear that they are always omgsocrazybusy and supporting two systems to any significant degree is pretty much out of the question. If the GSL were improved to their liking, I would expect GameMastery type products (item cards and other "tools"), but I would be surprised if they did much in the way of 4e
books. I suppose they might eventually toss an adventure or two out there just to gauge sales numbers (they are smart enough business people to do that), but I don't see even that happening for a long ways out, and unless the sales numbers make them drool, I'd see them still focusing 95%+ of their effort on Pathfinder.
I could see Green Ronin jumping on board with a better GSL, but they were moving away from standard d20 long before 4e came out and have enough product lines going strong to probably keep them busy for a long time.
That being said, I think it would be really great to see those two produce 4e products, I'm just skeptical that it will happen to
any significant degree regardless of how nice the GSL is.
However, with
small publishers, I imagine there's plenty. Heck, if the GSL gets better, I've said I'll switch from occasional freelancer to occasional publisher. Indications of a better GSL coming out someday have been good enough that I'm writing products now. However, I'm also keeping in mind that if a better GSL doesn't materialize, then I'm producing them all for Pathfinder instead. The lack of a GSL acceptable to me is the only thing holding them back. I'm pretty small time, of course, but I imagine I'm not alone in my sentiments.
But if I've missed some clear declarations of willingness to support a better GSL, from small or large publishers, I'd like to see them. Necromancer is the only that I have seen clearly indicate that they need a better GSL (and their website update yesterday makes it pretty clear that they think the new GSL is very close and acceptable to them, which bodes well for me).