Or, at least I wouldn't expect it any sooner than Warcraft IV would be coming out with WoW on the market. There's a good chance that waiting that long destroys any chance of seeing a sequel that's similar to the first two games. Most IPs that make the jump to successful MMOs don't have single-player titles releasing alongside them.

Then again, nobody knows. tOR could flop, which might make Bioware go back to its roots.