Not merging the two doesn't make sense. Both are aimed at hildonizing Meego and providing capable reference apps. Now, once that is complete there could be several different UIs. Cordia is aimed at getting the Maemo 5 UI on top on Meego, but that is just the start. Once the foundation is there im sure other UIs will emerge.

It just seems like a lot of wasted energy to have two people working on the same exact stuff (which they will be for the bulk of the project) without sharing information and combining their efforts.