I have an overbite as well (Class II), and I'm getting my upper 2nd bicuspids extracted on Wednesday, April 18th. SCARY, but I figure I'm as ready as I'll ever be. I plan on taking Valium the night before and the morning of to help prepare me...
I have been in braces about 4 months so far. My ortho straightened my teeth first, now we are extracting and pulling the upper teeth back. I asked my ortho about whether I would notice gaps btwn. each of my front teeth as the "big gaps" of the 2nd bicuspids start closing. He said gaps would not be noticeable btwn my front teeth and that he plans on moving them all together, but not sure if he's just saying that to make me feel better or what. I'll keep you posted.
Regarding the whole extraction issue and whether it's needed or not. I saw MANY (OK, 6) different ortho's prior to getting braced. 4 of them recommended extractions, 2 recommended lower jaw surgery instead. I did not want to go thru jaw surgery at my age (just turned 35), so I went the extraction route. I still have concerns about how my profile will look after it's all done, but I believe the change will be so subtle noone will even notice. Also, my ortho has said that by using elastics, the upper teeth will pull back a bit, and my lower teeth will pull forward a bit to help accommodate for the overbite. I think you should just trust the judgement of the ortho's you've seen. They know best how to treat your case. But I do recommend getting several opinions to help ease your mind.
One last thing, I've never been told that the 1st bicuspids needed to be moved first, then the rest of the teeth follow. I'll ask my ortho about this to double check, but I don't believe this to be true - at least in my case.