Coming not too long after a public outcry against EA's Origin service, for its invasive, spyware-like policies in its EULA agreement, Senior Online Community Manager Stephen Reid for Star Wars: The Old Republic via the official forums has stated that, unlike Battlefield 3 for PC, it will not require players to download the client:
Regardless of what other games may choose to do in their integration with Origin's desktop client, here's what our situation is:
You are not required to use the Origin desktop client to download, patch or play the game client for Star Wars: The Old Republic.
This applies whether you purchase The Old Republic via Origin.com or from a retailer in boxed form. You will not be forced to install the Origin desktop client.
There are still various consumer benefits to the client itself, but it's not required for The Old Republic.