Functionally there is no improvement in a home theater application in using 20A outlets. If you’re looking for something better, you might consider having them use commercial or industrial grade outlets. They are built better and have a tighter grip on plugs.
Not only that, but it may not be to code. General outlets thoughout the house should be on a 15A circuit. Only if it is not specified to be on a different one, such as a microwave or other kitchen appliances.
20 amp receptacles are physically different from 15 amp ones, unless you get 15/20 combos... The neutral (longer) blade slot is at 90 degrees to where it is on a 15, on the combos it looks like a T on its side. If you were to go with the 20s get combos so that you could still plug in 15 amp cords. 20 amp circuits would be larger conductor, this means less resistance and at best, absolute best conditions would mean less interferance on the circuit. Unless you really want to load up these circuits, there's not really any point in it, but if you plan on running lots of equipment, or high power equipment now or in the future, its alot easier during construction than to try and retro fit.
about tripping easier, i suppose they would, but i've seen 15 amp stablock breakers hold in at wayyyy over 15 A, like pushing 30, so its best to use common sense when planning on how you are going to load up individual circuits anyway, and don't put alot of faith in your breaker. They will definitely (should definitely) guard against dead shorts, but watch the overload!! (somewhat qualified comment, I'm a power electrican)
I agree with Tony. The only time you really need the higher current circuits and outlets is if you're running something mechanical on it, like an AC, blower, or some other large appliance with moving parts. For electronics, 15A is fine. If you do go with 20A, make sure it is end to end including 12 gauge wire (of course the electrician should know this). I use 12 gauge for all new circuit runs in my house. (BTW, I'm an electrical engineer)
There is nothing wrong with putting 20amp outlets in, however, it is something you will never use. All home stereo/theater equipment is going to have a 15amp plug on the end of the cord and as such will never need a 2oamp outlet. If it is going to cost more then you will push the envelope on "bang for the buck".
As for tripping, circuit breakers are protection for wiring. Does not matter whether it is a 15amp or 20amp breaker it will protect the same. The twenty will allow you a higher ceiling upon which to draw. Like Ken said you must make sure that you use the correct wiring for the breaker. 12 guage for 20amp, and 14 for 15amp. Oh, my reference? I happen to be the guy who handed Ken his diploma...Guess all of that knowledge wore off
Every breaker in my box is 20A. So when I was (currently still) remodeling my basement I just ran 12ga and added more 20A breakers... only using 15A style plugs on the wall however. As mentioned above, not many things have 20A style plugs on em.