I'm pretty arabivalent on the issue. If they want to sure, if not that's fine too. I normally watch/listen to them in Japanese though, unless I prefer the dub version to the original (as with the Blue Gender ED), which is admittedly is rare.
I think the bigger question is if the Japanese companies will let them. I remeraber hearing that Japanese companies asked dubbing companies to stop because they wanted to promote the original artists or something like that (I'm pretty sure that's why FUNi had to stop with Conan and One Piece). It could also be an issue of cost, between licensing and production I'd imagine it can get expensive.
I'm personally more inclined to want to believe the latter. Since Japanese artists usually don't get released outside of East Asia, I never saw much credibility in that argument. Especially since I'm fairly positive the artists on the labels in question (Giza and Avex*, respectively, who provide the artists that perform the themes for aforementioned shows) have never gotten released in America, Sony-signed (like L'Arc~en~Ciel and High and Mighty Color) and mostly obscure (or rather non-mainstream) Visual-Kei artists are really the only artists I've ever seen get American releases (digital or otherwise).
* = BoA attempted an American career, but that was sponsored by her Korean label, SME, not Avex.
