Very cool. But I wouldn't let the audience know from Vader that they'll be "waiting for them". Just enough to know Vader and Fett are involved.
Maybe fett could send the info rather than meeting up with the rebels? Might be more doable that way.
Still, freakin awesome!
edit:
good point about Boba Bingowings. Why would he stick around Jabba's anyway? Have him do his thing and take off.
Brilliant