Tablets/smart phones are terrific travel computers and offer a convenient way to browse, play games, maybe listen to music and podcasts and so on. This works of course only if you really don’t have to be productive and if you don’t mind tiny text, funky behavior sometimes, difficulty printing (ipad), inconvenient data entry, no flash, and so on. And in the case of Apple tablets, if you don’t mind being tethered to a company of control freaks.
For me I’ll take my tablet when I travel. But I will continue to use my laptop in my recliner sipping my morning coffee watching the sunrise. For people who have to be productive or serious gamers, they will undoubtedly continue using desktops computers or full function laptops.