I have used join.me in the past as a fallback for when a customer cannot establish a gotoassist connection. In the vast majority of the cases the reasons that the user cannot connect is due to some pet security feature that IT has established -- blocking all JAVA or similar restriction.
I'm noting that join.me is no longer the ""one click freebie"". User is requested to create a trial account, etc.
FYI - I know many people had used this previously. I'm still thinking that GotoAssist is working well and that the handful of customers that have not been able to connect are mostly due to IT restrictions on their end and not GotoAssist limitations.