I mean, conceivably one could imagine that there *could* be problems with dozens of people that many of us don't know on the same webspace, if you put it like that. Then you remember we've had the same thing with Mafia community influxes and you lighten up(Also, all the scenarios where I can imagine actual problems coming up are very outlandish, to boot~). So yeah. Strikes me as a fine idea.
I don't think there are any realistic concerns on our end. They're not planning on linking ROMs or pornography, so our host won't kick us out for content reasons. They're not planning on hosting 1080p live streaming video on the DL proper, so we're not likely to hit any bandwidth restrictions.
My only real concern is actually "What if their forum goes completely dead, and everyone leaves and stops posting?" Knowing us, We'd keep it as an archive, of course, but every once in a while we need to upgrade software for security purposes, or a spambot would get through the filter, so we'd need to do maintenance, which is a bit of extra work for Tal. Still a fairly minor concern, all things considered.
No, I'd say most of the question marks are on their end, not ours; are they willing to trust us with backend admin controls? Do SMF controls give them enough control, or would they want more extensive admin abilities?