Vote for the Eclipse Release Train Name (2007). There has been some discussions in bugzilla.
I think Europa is a very bad choice for two reasons:
1. There are too many Google hits already if you search for eclipse europa.
2. In many languages Europa means Europe and this will confuse. Messages like the "Europa Build Workshop", sounds for many non-native speakers like "The Build Workshop Europe". If English is your native language, you might not understand this point, but for Germans this is very confusing. For the same reason you would not call a workshop held in the nice Austrian village called Fucking the "Fucking Workshop" ;-)....