Don't know the percentage but there a ton of guys that commute at UPS from every city in the U.S. and from all over the world. Being junior would be especially unpleasant if you have a difficult commute but not bad at all of you have an easy one like PHL & EWR and/or ATL to SDF for example. There are quite a few newbies commuting from the west with relative ease as well. As far as ANC, it's relatively senior so you really shouldn't have to worry about it if you don't want it.
For the most part we don't have any bases that make for an easy commute on the pax carriers so utilizing company jumpseats tends to be the preferred method. Check out:
http://inside.ipapilot.org/tools/jumpseats/index.php
This is our Jumpseat schedule and you can see what a potential commute would be like. Times are in Zulu, sorry. The general motif is that flights leave from outstations early evening for Louisville and other hubs (sorts) arriving there sometime around midnight and fly back out around 3am. They do this Tuesday am thru Saturday am with nothing on Sunday and Monday; exceptions exist. Lots of trips start at 2-3am in a sort city so you can Jumpseat in if you can be adequately rested. Quite a few trips end around midnight making a commute out on company easy. Otherwise they commercial you to an outstation or back home from one to start or end a trip leaving only a small percentage of trips which are not commuter friendly. Being junior, you will probably get awarded lines that are not commuter friendly or more accurately, not commuter easy but certainly doable. The angry-man from earlier on in the thread probably has a difficult commute with an unfriendly line. Being one of the new hires in the latest round of hiring I agree that anyone looking to come here should consider the commute you will endure being junior and whether or not you are willing to relocate at least temporarily before committing to coming here.
No rumors about new hire classes. General consensus is that once a TA is produced or a contract signed is when we will hear about classes, if any. Rumor for a TA presentation to the pilots is sometime in the spring. It would seem that they keep interviewing solely to maintain the pool as few are waiting around for a call from UPS and taking other offers as they come. If you give us a specific city you want to commute from we can give you a better idea what it would be like.
Best of luck to you in you job search!!