In an interesting interview with a Sony executive, it appears that Sony's long term goal is to have "PlayStation" be a service as well as a hardware platform. Using their Gaikai tech, they envision streaming games to PCs, tablets, PlayStation hardware, etc. With this news, everyone's PlayStation account could be the equivalent of a Steam account.. and instead of downloading a game from your steam library and then playing it, the PlayStation service would allow you to chose a game from your PS library and instantly start playing it / streaming it from the PS Gaikai servers.
Sources: PSU.com & Dengeki Online
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