Though Greyhound may have changed its schedule in the past eight months, there was definitely a stop at BTV on the Boston-Montreal bus route when I last took it.
It would probably be pretty nice to get on the bus there if one flew into the airport, since it's less than 2.5 hours one way from the airport to the city, but it made an already interminable bus ride even worse for me.
There's also always that one person who has issues at the border and makes the entire bus late. I got a "Why were you in Canada last week?" but that was easily answerable and I didn't cause a delay.