It would be a pretty bad idea to not instate new servers when you expect a large and sudden increase in players, such as when releasing it for a new platform. This is why it only makes sense to open servers along with the PS3 release. This does however not mean that they will be exclusive to certain platforms.

Just imagine how it would be if the player base more than tripled practically overnight, but the new players all had to come to the existing servers. You think uldah is packed now? Imagine how it would be with 3-4 times as many players per server. That's how it could turn out if they didn't open new servers along with version 2's PC and PS3 release.