Sometimes I stumble upon a preview of a game that looks nice but doesn't have a fixed release date. As I don't follow too closely new releases, I end up forgetting about it and never playing the game. Is there a website that allows registering to get an e-mail notification when specific games get released? Ideally, the website should quickly add newly announced games to their database and include XBLA/PSN/WiiWare games. Indie games would also be nice. Do some of the big sites like IGN, GameSpot, GameTrailers, etc. offer this feature?
When It Drops is a site that lists new release of not only games, but DVDs, Movies, Music, and Books. It's a tumblr site, so you can follow along in your dashboard if you're a tumblr user as well.
They also offer an RSS feed if you use RSS.
If you're specifically looking for e-mail notifications, you could tie it in with a service like ifttt (currently invite-only, but I was invited pretty quickly) to fire you an email every time the RSS feed updates.