Just a quick follow up report to my questions in this thread: http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=78416
We hiked from Devil Creek trail head down to Elk Lake, Moose Lake and Jims Lake (behind Elk and below Forester Mt) on July 6-10. The daytime temps were in the 70s, overnight in the low to mid 40s. We found occasional patches of snow in the lower elevations and larger patches up on the ridge lines. The creek crossings along the route were not a problem - none even required changing shoes. The flies were very thick but did not bite, mosquitoes were out at dusk but not too bad.
We did not make it all the way to the middle fork but talked to the ranger station a few days before the trip. They said their trail crews had crossed the river near the Castle Lake trail by raft but did not expect to be able to cross on foot for another week or more.
We did a quick drive through GNP on 7/11 - there was quite a bit of snow in the higher elevations and some patches/piles at Logan Pass visitor center, but surprisingly little considering the pictures we had seen from just two weeks before.