I hiked the Franconia Notch Trail, Mt. Lafayette, with a friend back in November 2010. Still the most beautiful hike I have ever been on. Once we broke the tree line, everything was iced/snowed over like a winter wonderland (I don't think you will run into that issue in the summer! Lol). On our way back down from the summit, the sun broke out and the scenery was insane, cameras stopped working at that point though... here are a few pics on our way up to the summit.
We planned on doing Mt Washington the next day, but a snowstorm came through the night before and the trail was closed. I plan on making it back at some point to do it though! Good luck on your trip!