I dont think its a gimmick. I would use it for work all the time. My meetings always involve some sort of documentation, budgets, reports etc and I tend to lose the notes I take on these documents after a few days. Being able to electronically take notes and arrange them in various folders and email them around would be absolutely awesome. That being said, ill wait a little and see what Asus release. Its definitely the tab I will get though, unless HTC come to the party with lessons learnt executed to create the ultimate tab.
I love the keyboard and see it as an awesome netbook replacement. Ill still use my work laptop though because of Office but that productivity suite should do just fine.
I'm excited!