I hear you. having recently outed my rythm player for the last 3 years and bass player. i did it by phone, but the way it was done, it was almost too easy. i guess it was their time to be out! we recently got a new bass player who is frankly much better, and we're planning on replacing my rythm and harmony guitarist by a keytar wielding buddy :D for original compositions, it works. for a cover band, i don't think it'd be as simple.
it's the way it is now i guess, everyone's tweeting and texting, might as well do the dumping this way. it's ''hip'' ;)
have fun on your gig, a cool lineup definitely brings a new energy the the band. i haven't headbanged and loved the tunes as much as the recent rehearsals :D hope it's the same for ya