Everyone likes a party, and CTIA provides ample opportunities for festive networking.  Yet shrinking margins have lead to a downturn in wireless carriers attending industry events and many vendors and investment professionals have followed suit.  Nevertheless, 2011 may be year to come back. LightSquared will announce…something.  The talk on the street is about a Radio Access Network (RAN) sharing with Sprint.  Most speculation centers around a simple space sharing agreement, but new technologies (see below) and…