I still think that PSN is the best option.
Think about it. With XBLA, it would indeed be possible, too, but every single mod (and I believe that Mods will play a BIG role in Aquria's future) would need to be put up there as approved DLC. So only the real top-notch quality mods approved by Alec, Derek and Microsoft would be up there, and probably cost 200 points :p
With Wii, you could be glad if you could download the game at all. The setup file for PC alone was about 200MB. That is almost half of the space the Wii has already. To that, what wingzero said about Wiimote controls isn't quite untrue. I mean, yes, they aren't a wobbly mess of craziness, and after some getting used to will work just as well as the mouse, but I can see it becoming a problem in hectic scenes, especially when there's a lot of accurate dodging required.
With PSN however, we'd have everything we need. The hardware requirements are easily met (360 and Wii do have that too, though), the space is there (even on the smallest PS3 version) and, most importantly, we'd have the ability to play mods quite easily, from what I can imagine.
Just put the mod on your USB stick, plug it in the PS3 and Aquaria can read them off there.
From my knowledge, the PS3 is the only console where this would work "just like that".
OK, granted, not many people have the PS3 and it's isn't the most popular of consoles either, but you can't deny its popularity is constantly rising and with the introduction of the 40GB model, more and more people are getting one.
In about one year, the PS3 will most likely be as widespread as the 360 is right now. And I don't think we will really see a console port anytime before then either.
So, yeah, not dissing any console here, I just worked out what appears to me to be the best solution :p
