I actually don't see a network change in the foreseeable future.
WWE has a good relationship with NBC/Universal, where they provide the highest-rated weekly show on two of NBC/Universal's top cable stations (Raw on USA and Smackdown on SyFy).
What happens in Europe and the UK, I have no idea. I don't think WWE's changed networks over there in a few years (totally ignorant on that, to be honest; I don't really know, I just know I haven't heard anything), and I figure they'll stay on Sky.
If/when the WWE Network gets launched (funny how I haven't seen a single ad for it over the last couple of months when they seemed to be pimping it hard around the first of the year), all of this could change, especially if WWE Network is backed by/part of NBC/Universal in the final analysis, which is probably the only way it ever makes it as a success.
wk