I've had my pIad for a couple days now, and the most interesting thing is how much it's like using a laptop. Mainly it's a matter of size, the fact that I'm using a keyboard with it, and I'm doing more laptop/work-y things. Safari also functions differently on the iPad than the iPhone: you can actually use Facebook and Typepad through the browser, for example, rather than using the dedicated apps. (And unfortunately the Typepad app doesn't seem to have a landscape mode.)
Oddly, the Typepad page doesn't have a WYSIWYG mode on the iPad, but it's just a chance to remember HTML tags.
Interestingly, I need to be a little more attentive to ergonomics and posture when I'm using the iPad + keyboard combination: it's easier to put the iPad slightly to one side and have to crane my neck to see it, or set the keyboard in what turns out to be an inconvenient place.
But for some things, I'm already starting to favor the iPad over my beloved laptop. The fact that it starts up instantly makes like it a little more appealing. We'll soon see if I can travel and write with it without losing any important functionality....