Not even close. Shitty screen, as it is now is riddled with software problems, and even if you stick a different OS on there you're not going to have usable battery life (its what 2-3 hours with the stripped down setup it comes with). All that for $500? Yeah, no thanks. Oh, and I forgot to mention, who knows how Fusion Garage is for support, let alone if they'll even be around long enough to support it.
The Courier is cool, but its just a concept so far, and while it seems that Microsoft might have realized people would want one and are still developing it as an actual product, it will be a while before we'd be able to buy one. By then it'll be like the Zune, cool, but it likely won't live up to its potential.
There are two major points that I like about the iPad, the IPS screen and the battery life. The price is a bit much for me, but something tells me most other companies will not get both things right. Also, it would seem that Apple's touchscreens work a bit better than other companies'. There is better touch tech out, but the chances of a company utilizing that, getting a good quality screen, having good software, being not huge, not even more expensive than the iPad, and having great battery life just is not going to happen. Instead, we'll end up with a bunch of crap running Netbook hardware with cheap screens and an OS not aimed at touch usage, smartphone hardware with poor software support (Google's OSes are not ready for a product like the iPad), and a bunch of other junk. The best I've seen was a Tegra 2 based one, but I'm going to guess it will have a crappy screen and not be stellar software wise and likely have not too great battery life.
I'm not even saying the iPad is perfect. I hate the screen resolution. I hate the addons (should have had a MicroSD slot...), its too pricey (I think Apple basically even said they left plenty of room to drop the price if its not doing as well as they hope like they did with the iPhone), and it just needs time to be properly considered as a platform (apps, prices, web content). It is however, likely to be the best overall experience of lightweight tablets for a while.