Guys, happy to report that I cleared both borders with ease..took perhaps all of 10 minutes at each point. I was not charged anything for the Lebanese visa. I did have to pay the departure tax. The total journey time from Beirut to Amman was 12 hours (a LONG day!), starting at 7:30am, 3 hour layover in Damascus and 5 hour journey to Amman. Contrary to info I had heard earlier about all buses terminating at Tarabour, the bus (Challenge company) stopped right outside Abdali station walking distance to downtown which was really convenient.
aoia, it's certainly possible, a lot of people on the bus apply for a Syrian visa at the border but some are refused. It's a 50/50 shot. I would say your chances of getting one are higher here at the Masnaa crossing (Beirut - Damascus) rather than the Bal-al-Hawa crossing up north which is very chaotic. The Beirut to Damascus border crossing is not too busy.

