A very good friend got an invite and bought the OnePlus One phone. Yes, you need and invite from somebody who has an invite code available. The invites are given at some time by OnePlus team to individuals who already own the device and sometime randomly thought their online <forums.
I had a chance to take a closer look at the phone this weekend. I like the phone. I like that it is an open (unlocked) phone. The current model can’t be used with Verizon though. The feature list is impressive and it runs CyanogenMod firmware by default. So if you haven’t heard about it check it out!
Now I have to find somebody with available invite :)