Amazon says that they're shipping my books on June 10th. I elected for the free shipping so I don't know when they'll arrive. However, my wife and I have agreed that we'll need an extra PHB (in addition to hers and mine) since all of our gaming is at our house, so I'll probably buy one on the street date as well.
Our regular games will be going on hiatus for a couple of weeks just after the books come out because of a family trip back to Ohio, so I'll probably have some time to read the rules before gaming.
My brother in law will run a character creation session for our new campaigns while I'm in Ohio. If possible, I will be on the cell phone with him (or maybe a video chat) while the rest of the group is doing it.
I have to say that we're not just stopping our 3.5 campaigns before their natural ending point. Luckily for us, all of ours were approaching that point. On Fridays we've had one FR campaign come to a conclusion (after completing a conversion of the old Against the Giants series) already. Our Shackled City campaign has only 2 more adventures remaining, and my Sembia (Return of Auppensor) campaign has only three more. We may be done by June, or we may not finish until July.
Our Saturday group is still finishing up its Eberron campaign and an Age of Worms campaign (just 2 more adventures). The GM of the Savage Tide campaign will be writing an early conclusion for us (we're about 12th level now), but that's because none of us like the storyline (GM included), not because of the new edition.
ASAP after the 4e release, one of our Saturday GMs will run the new published adventure. We're going to wait until we have the PHB because we'd rather build our own characters.