It looks like all of the predictions were right! Today BioWare has officially announced that Star Wars: The Old Republic will be going free-to-play this fall, with players having full access to all eight personal storylines up to level 50, although some content and advanced features will be gated via microtransaction purchases. Subscriptions will still be available to players by offering unlimited access to new features and higher-level content, but BioWare has noted that they want to offer "flexibility and choice" to their players.
Ultimately, according to the new SWTOR F2P FAQ, free players will be limited in terms of how many warzones, flashpoints, and space missions they will be able to accomplish per week. Additionally, F2P players will have "extremely" limited access to the Galactic Trade Network, as well as no access to any endgame operations. The expectation is that these features will be available to F2P players via microtransaction purchases (BioWare is calling their real-money currency "Cartel Coins"), but subscribers should be able to access all of this new content for the same monthly price.
BioWare also has plans to reward their current and returning players, with Cartel Coins rewarded to subscribers and purchasers of the Collector's Edition of SWTOR, as well as a unique "Fan's Choice in-game item" for anyone who subscribes before August 1st, 2012.
You can check out some of the new upcoming content coming for Star Wars: The Old Republic here.