Yeh, I put them on the list because I do think they'll slide into the third slot. Their deal with Nokia gives them good reach, especially in emerging markets. Also, they have a huge warchest of funds and the patience to loose piles of money in order to get market share in an important market (XBox, Bing, ...).

RIM has much more marketshare in developed markets, and it can still turn things around.

WebOS has a technology advantage over Microsoft's offering, but a bad starting point. Still, I would not rule HP out.

But to be honest, I am not sure third place will be a significant thing. The mobile market is looking to repeat history with how things turned out on the desktop. Do we care much about third place there? Not really.