On the other hand, 5-man (or more) expeditions would fit quite well into the game. Dungeons much like those in SWG. I think it has become too conventional that a MMO game has to contain elements requiring 20+ people. This of course has its pros, but I definitely don't find this fundamental.
When I played games like SWG or COH back in the days, I rarely even entered a dungeon at all. This was probably because of the game style being all that new to me. I didn't know what the game had to offer, but I enjoyed myself so much.
My point is, I hope that TOR will offer something new to the MMO experience. There must be something that can keep people busy, without having it to be late night raids on scheduled week days. Though, I'm not keeping my hopes up too high about this, since most new MMO games are just concerned with obtaining a level of competivity with WoW.
WoW also did keep me busy for almost 4 years, but when I now am going to start something new, I'd be sad to see something all too similar with WoW.