I looked into tablets and netbooks for a while... seriously, netbooks offer so much more for less it is hard to justify a tablet. I have plenty of disposable income sitting around but I just can't justify a tablet. It really does not offer anything a netbook can't do. Also, something about spending that much for a large smartphone (when you already have a smartphone) does not make any sense.
Right now, for me, the best combo seems to be a good netbook for traveling + Desktop for anything home related + a smart phone for true on-the-go activity including GPS. Other acceptable combos are Laptop + smart phone or even just desktop + netbook + normal phone is fine for most people and reduces redundancy.
Tablets seems to have too much overlap with smart phones to be anything other than a way of complicating your life and wasting money for no reason.