I have been using my Ipad mainly for work, for almost 2 months now. So far my experience has been pretty pleasant. I mainly use my ipad for:
- referring to price list/ PDF/ Office documents
- jotting down notes during a meeting
- go online whenever i need to (especially when i need extra information other than those i have prepared beforehand)
- emails on Exchange Server 2010
- presentation to clients (via Keynote)
- occasional gaming during travel

To be frank, all things listed above can be achieved with a normal net book or laptop... But one thinf is for sure, my ipad can run for 3 days on 3G until it needs a recharge... This is not achievable on any other computing device.