It depends on what you want it for, and what type of tech level you are. While the iPad is less versatile, I have recommended it to a friend who just isn't very technically competent. They're good for those with less technical knowledge.
I've got the Asus myself, and the ability to lock on the keyboard and type (as I am now) is an absolute boon, plus it works as an additional battery/charger.
It can play any media type, and while the Flash plugin is no longer being updated, everything on the web works. I get to use the full desktop versions of sites, which you can't do on the iPad. The overall browser is better even without Flash.
Android Apps tend to be cheaper, if that matters.
Downsides? It's not glitch free. I've got no showstoppers, but there's a battery display bug I keep getting that means I have to take the tablet off the keyboard and reattach it (2 second job). Also, the google checkout for the apps is painful.
That said the iPad is not bug free either. While it does generally "just work", Apple has a tendancy to change things as it sees fit, so the recent update breaks shared secure calendars on private servers, because they have decided you need to use their paid for service instead. If you're happy with doing things the Apple way (and millions are), then the iPad makes sense.
If you prefer more freedom, and want more control, then the Android. I've used both extensively, and I went for the Android, but I'm pretty geeky.
Oh, and while I don't disagree with most of Jayaramd's answer, don't make any decision based upon their OS version numbers. As they are completely different, one being version 5 and one being version 3 makes no odds. In terms of functionality, they're very close, except for the limitations placed by Apple, such as file format support.