Non-cross-platform != bad.

Doc says, "IE5W exclusivity is evil." He points to OddPost, the groovy new web email app that's getting all the buzz but is only available for Internet Explorer 5+ for Windows users. I've heard these kinds of sentiments from others, but I don't get it. I can see how it's annoying if you can't use something you've heard is cool. But it's not evil. I'm all for cross-platformness, but I also don't see the harm if someone wants to take advantage of some kick-ass functionality that exists in IE5W and no where else. If they didn't, the product just wouldn't exist (or would exist in a less-interesting way) and no one would benefit from the cool functionality. Interesting, you don't hear these complaints if a piece of software is platform-exclusive but not delivered in a web browser, which is really an arbitrary technical point. If OddPost is evil, why isn't iTunes, or HomeSite?