I want to like Impulse, because it's a decent service, but they seem like the least interesting one these days. GamersGate has pretty good deals (like a daily deal) pretty much every day, Direct2Drive is getting some really good deals too recently (lots of big publisher stuff 75% off), and GOG... well, GOG doesn't really compete directly with the others, but they too have been having great deals and new releases.
But then I go to Impulse, and their sales are always really boring. This week's weekend sales? The 'eGames Burger Pack', whatever that is. A Sherlock Holmes Sleuth pack which seems totally uninteresting. And some small discounts on their own PC-software-stuff. And this THQ Pack thing, too. It's like they're not even trying to attract customers anymore.