I think the reviewer has a point... for as long as this game was in development, how does it manage to add nothing new to the genre? It doesn't mean it's not fun or a good game, it just means it should have been out 2 years ago. That being said, the writer himself admits he's only in Act 2 when he wrote that. Perhaps his view will change in Act 3.
SC2 has been on sale for $30 in the past though, a price I am unwilling to pay for that game but more likely to pay for Diablo 3.
But again Blizzard has not been seeking to make big gameplay changes to any of its recent titles. For those of us that still played the originals that's more than enough.
However, it certainly would take a long time to generate all of the art content for the game, and I'm sure that's where the vast majority of the development costs went.
So if the complaint is "there isn't anything new or revolutionary about this game" then I would argue that you weren't the demographic that this game is targeted towards. You're playing the wrong game. It's a nostalgia trip, and nothing more.