treks are a great bike!! highly recommended! are big in the x country scene (well they were..) the trek reps are great and they DO take the time to look after you should you have any issues with your ride.
Once you recieve your bike, it SHOULD be in a relatively tuned state, that said, if you ride it daily for a week, thigns such as brakes and gears will need adjusting as the cables will stretch alot while they 'bed in' its a normal thing on a brand spankin bike.
As with anything, keep up the maintenance, treat it like it should be treated and use it for the purpose its meant for. Its not a DJ or downhill.. dont expect it to perform or be as strong as one.. but it will happily take you 100 country miles comfortably without any hassels.
If you do plan on doing long 'treks' (funny bugger i am) its worth getting the bike set up to you, go down the LBS and ask them about seat heights, bar length, stem length etc, and get it dialed. Its well worth spending that little bit extra time for the comfort in the saddle!
that said.. Happy treadling!