Running in a WIN7/IE8 (no chrome support), the browser (from which I'm writing within) is responsive, the productivity work stack is sufficient and the multimedia capabilities including youtube HD were as expected you would expect on bare metal.
... Leading to off course to the "ubiqoutus slate" evoloution that the Ipad will create and catapult into the mainstream. After a number of less than successful tablet implementations, the market seems poised to benefit from the marketing/content market that Apple has developed Iphone/Itouch ecosystem.
Applications such as ICloud.com will become the killer application for Tablets which are what Ipads will become. The need for the horsepower (like the telephone system) is in the cloud.