I posted this over at rpg.net and got very little help. I'm a 2nd ed GM from years ago. I've got 4thed and my players want me to run a game.
The ~problem~ if you can call it that is we are 8 total. 7 players all of who will regularly turn up. [I know I'm blessed!]

Issue is how is this going to bog down? Is it really too many players? What is the sweet spot?
If I'm going to go ahead and run it at this number what are things I can do to help things resolve quickly? Or as quick as possible?

This linked thread had some ideas.

Much thanks. My search-fu is apparently weak. 8(

FWIW, I used to game with Rob Boyle. His Shadowrun campaign often had 5-7 players at the table. I'd expect he's at the upper end of GM skill (duh), but it went pretty well, as long as there was minimal inter-player crosstalk and the team worked as such, rather than getting into back-stabbibng.
A few of his Earthdawn games had 12+ people at the "table". Much simpler system, obviously...

Yeah as long as the GM keeps control and the players stay focused on the game and don't go off on tangents 7 is about the upper limit. The much better 4th ed decking rules should keep this ok, using the old style decking rules it could be nighmarish.

My group also has 8 total people, 7 players and a GM, and it gets pretty hectic at times, but it can be run well if you've got a good GM. For us, he tends to set things up so that we can split into two or more parties, and he'll focus on one party at a time for a little bit and then switch. Combat does take a while, but that's the price you have to pay when you're playing with upwards of 5 people. Definitely buckle down on cross-table talk, and MAKE SURE everyone is paying attention. For a while, we had a big problem with laptops, and everyone almost always started their turns with "What's going on?" Not a good thing. It's getting better now, which shows that big groups ARE possible, they're just a little bit more work.