The latest class isn't a great reflection of what to expect, but the class of 12 all got 737 EWR. Their nickname is 'the Sewark 12'. That's a one-off IMHO; most classes have been 737 EWR and IAH (a few 756 EWR) and everyone who wants to go to GUM, as long as they talk to someone on day one, will usually get that. What happened in my class is two IAH 737 slots were converted to GUM slots.
GUM - not voluntary, but if as long as some newhires raise their hand and volunteer, there shouldn't be invol GUM slots. The base isn't big enough (and there's not enough FO movement out of there) to force invols into the base.
145BOSS posted unfilled vacancies from the latest bid. Those should end up going to newhires. However, there's an issue of LUAL furloughees and seat locks. Some of us want to bid off of the guppy and over to fifi; I don't know of anyone who was able to. I have a standing bid for fifi out of LAX and my 24 month guppy seat lock ends in a few months.
We could get into a debate over different aircraft, but I much prefer fifi over the guppy.
For any newhire, I highly recommend avoiding the 756, as you'll be on reserve forever. And reserve sucks. Stick with 737 or A320 and wait until you can hold a bigger aircraft off of reserve.
It's going to take a while for everything to shake out, but the bases that I'd expect going junior in the future are:
EWR - Sewark by a mile. Toss NYC into the mix, as that will all be the same.
IAH and SFO behind EWR
ORD - it may be senior for a little while but once the hiring machine gets in full gear, ORD will become easier to get
The hardest bases to get:
SEA - I think every FO there could be in the left seat anywhere else
DEN - There have been some newhire classes with DEN in the past but there weren't many.
CLE - Small base; most pilots seem happy to stay there
Middle of the road
LAX, IAD
For any newhire that desires to go to somewhere like DEN or CLE, I'd recommend bidding guppy. Add A320 for DEN. That way you should be able to get a lateral to that base.
Don't take a 756 if you're thinking about taking a lateral. You'll probably be stuck at that base for your entire 24 month seatlock. On reserve.
Hope this helps; please remember that things can change on a moment's notice so this information will probably be out of date as soon as I hit send.