We seem to be in the tail end of a consolidation phase right now, the one the article is about. I think it's largely brought on by the final commodification of the internals of a phone/tablet; even a $50 Amazon Fire tablet is now a decent tablet, something that wasn't true in that price range two years ago and perhaps even one (I wasn't looking then so I can't quite vouch for it). (Yes, it's probably subsidized a bit, but it still ends up setting the bar.)

Once that completes, I'd expect the market to expand a bit more as companies seek ways to stand out other than "we have the cheapest thing".

But you may never again see a "phone" with a physical keyboard. Too niche. Instead, you'll have to look for a case with integrated keyboard or something: http://www.amazon.com/Sliding-out-Wireless-Bluetooth-keyboar... I don't think it'll ever be economical again to produce a phone with a keyboard built in, but that niche can be filled with orders-of-magnitude-smaller runs of keyboard cases.