This will probably never happen...let's not forget General Electric is doing paperwork to sell/give/trade/etc a large stake in Universal Studios from NBC to Comcast(GE owns NBC. NBC owns Universal).
NBC doesn't own Universal, NBC is Universal. They were merged. Comcast bought NBC-Universal.
Let's set the record straight here. Universal Studios is a division of NBC Universal. NBC is also a division of NBC Universal. Universal Studios is not being sold from NBC to Comcast and will continue to be a division of NBC Universal.
Pending final approval, Comcast is purchased a majority stake in NBC Universal from General Electric. General Electric purchased a 20% share of NBC Universal from Vivendi. NBC Universal will be a subsidiary of Comcast with General Electric being the primary investor, owning 49%.