The beta does not start until the 25th. You will not be able to download the client until either a day or two before the 25th. That is how the previous beta weekend I was in was done, and I see no reason why this one will be any different. It's true, this probably should have been worded as such on both ZAM's and Bioware's site, but still.Be patient, padawans.
Signing up. Let's see what happens. =)
After getting the key last week I was on wait-mode on when the next test starts. Logged in just now to merely check if there was any news and yes, there was a test weekend invitation pending. Accepted it and downloading client right now. Excited!
Rather poor communication from Bioware and I hope not a sign of how they plan to manage the game. Have to wait and see how it pans out around the 25th
The client is available for download now at http://www.swtor.com/tester so if you signed up, you can start getting the game client installed and patched.