Yeah that whole Dolphin thing was weird. Seemed like valve just didn't want to deal with the legal headaches of fighting Nintendo in court over an application that didn't really need to be on the steam store in the first place.

Can't say I blame them really.

Personal opinion time: I don't think emulators belong on a commercial store anyway. Keep them on their own websites or Github. Putting them on a store like steam is just asking for trouble.