N-a-B - I would second the comment that POGO, overall, has been a better source of information over the years than LM or the program office.
The fusion issue remains a bit murky. Apparently the "patch" that allows four aircraft to share targets involves Link 16, which works but isn't very stealthy, to say the least.
The Marines are also falling back on the "it's much better than what we have now", which is not a huge deal, considering that they have AV-8Bs (1970s-80s with no core avionics upgrade that I can think of) and falling-to-bits F/A-18 Classics. They used the same line for decades comparing the V-22 with the CH-46.
One general observation: when the Marines and the AF talk up the wonders of the F-35's situational awareness and sensor fusion, consider that almost all their aircraft today (the F-22 is the exception) have early-80s, first-gen-glass cockpits. Aside from the F-22 the only U.S. type that has some degree of fusion is the Super Hornet, and guess which service is the least excited about the F-35...