Dota2 to become keyless economy come 2015

Because you can't withdraw money from your Steam Wallet, its essentially points already.

yea even i was thinking the same i mean hundreds of thousand of worth keys are traded all day

Valve still gets money. Games have to be bought sometime. Even if they make keys go puf, people could easily trade through paypal.

The real problem is for people that have hundreds of keys of Dota2 from trading and have never played the game thus having no idea what to do with them.

You have a whole year to deal with that, you better wait a good new chest, redeem the keys and sell the parts on the market, it's the safest way to go IMHO. If you have few keys, I think you will have a short window to sell on the market, as the price of the treasure keys will bump when when a new chest is out.