An update for anyone that might want to try the game out. They enabled the f2p trial accounts today. Any old trial accounts did not get re-enabled, so if you had one before you can't use it anymore unless you pay to upgrade.
I tried it out with making two new trial accounts. The process to get the first one actually enabled as a trial was a pain until I went to the main site and clicked the Play Free link on the right. I used it directly for the second account and it went smoothly.
In game I made two bounty hunters on different computers and was able to invite without any issues between two trial accounts. So boxing trials shouldn't have any major issues as long as your software/hardware works for the game. I saw a post on another forum saying trials couldn't be in groups or join warzones. However Bioware's trial FAQ mentions nothing of either one, and invites did work fine. So hopefully Warzones will work fine once your level is high enough.
Also currently all expired accounts have free time until July 17th to play.
Edit: Regarding invites, I had both chars on each others friend's lists, and invited by clicking on the toon in-front of me and inviting to group from their portrait. No idea yet if only this method works as I haven't had time to play yet tonight.