I think that at the end of they, it will come down to the developers. And by that, I mean the companies (with payed designers, graphic artists, testers, sales and marketing ppl). They will come only if there's a bussiness in the platform: enough cheap devices for a sizeable market.
So we'll see; if in 2010 there will be multiple maemo phones with different featuresets and different pricepoints, then yes, maemo can be a contender; otherwise will remain a niche os on a nice device.