I haven't seen any announcements of new routes RDU.

In all the years I've lived here, the only Saturday/Sunday-service to leisure destinations that I recall are: CUN, MSY, and LAS

That in addition to the seasonal (sometimes daily, sometimes not) to TPA, JAX, MCO, MIA, and FLL.

I've never seen them fly anything to the Caribbean from here -- it would be awesome but I don't see it really happening. Don't know that there is a big enough leisure base here to support direct flights vs. the short hop over to ATL (ditto with AA given how close CLT is). The obvious one to me if they did put something in place would be BDA -- it's closer to RDU than it is to ATL.

I believe F9 and B6 are both offering directs to SJU right now that's about the closest thing that exists.