I don't think "more of the same" is entirely fair. Yes, most of the elements are the HL2 ones (a few new enemies and enemy/ally behavior) but that's not the point. The way Valve makes games, every situation is a little new and different from a gameplay perspective. There are fights and situations in Ep1 that were not in HL2, because they thought of new ways to combine different elements into something unique. What's there that's old is perfected and polished. What's new: having an AI character who is a true ally and situational companion, is something pretty neat and worthwhile. And, as always, the teases for what's to come are great (the "pod," the Ep2 mini-.... well you know what I mean.