Added, keebs. Dude, why weren't you in the OWnet group to begin with? I thought we posted all that stuff. Anyway, you have an invite. If a few more people get L4D, we could even get some versus multi happening.
As of now we have enough for a full survivor team for coop, anyway. You, me, Pyro, and Idol. We have no confirmation whether Idol can play consistently with his connection, but I'm hopeful. I've seen reports of dialup guys playing the game and pissing off LPBs, so hopefully we can get it going without too much problem. Time will tell.
So further update: I actually found the single player quite fun. I don't know what's up with all these people talking about how if you aren't playing with other people it's totally worthless. I played through the first episode (they call them maps... but it's really a series of 5 maps, so...?), and I had just as much fun as when I played with Pyro. I can even see playing with other players more annoying because they won't do what you want them to and will likely get you killed more often and avoid helping you out in favor of trying to play the hero. The bots can't seem to pick up explosives, which is a drawback, but that seems to be the only real limitation aside from the fact that you can't get them to lead and they won't use stationary guns, making that your job in all respects. But they're pretty good with pathing and following you 85%-90% of the time and are never far off even if a little behind, and they're very conscientious about healing you, healing each other, sharing supplies, and reviving teammates. Not as good as human players no doubt, but there's absolutely no reason you can't play the game with them. Multi is obviously where the meat of this game will lie since it's so blisteringly short, but if it gets cheap later and has DLC, I imagine you could get on with the SP well enough. It's not like you'll just play it once. I had as much fun on my 2nd run as I did on my first. So that's about 3 hours total fiddling, and I haven't even seen the other episodes yet.
Anyway... my outlook gets more positive as I go. Hopefully the trend continues!