I really doubt they'll last as long as consoles have though. The thing I see for tablets is improved processing power/storage/graphics. They're also obviously going to keep getting thinner. But I just think the novelty of tablets might very well wear off for most people. The amount of things you can do on a tablet is limited to the device's touch-based nature. And that will not be changing any time soon.
used a surface/surface pro?
ipad with a keyboard?
they are very good PC replacements for most people