In a move that isn't fooling anyone, Verizon is jumping on the open bandwagon. They have followed the lead of Sprint, and will allow any CDMA handset to join their network by the end of 2008.
Most proponents believe this move will be a first step in the road to having networks like the UK or Japan. However, those networks are more similar to one another than the networks here in the US. Handsets will not really work cross-network as easily as our Japanese counterparts, but we'll see where this goes.