Yes, but the US spec ones first came in 2000, so nothing really to worry about in that sense. They still drink oil regardless, I always had to add a quart halfway through the synthetic oil life cycle (~2500 miles), especially if I decide to have a few quick high speed runs.
Not necessarily, BMW 'recommends' to use their oil, as well as their tune up parts (i.e. they're expensive spark plugs and hoses) when its really just BMW wanting more money from me and other owners. BMW is known to use re-branded bosch parts, which are parts you can find at NAPA 3 times less than you can find at the BMW dealer.
Using any good quality synthetic, i.e. mobil 1, valvoline, etc, and the correct weight (they recommend 5W-30, but depending on the season, I can use 10W-30) it doesn't really matter. Just keep up with maintenance schedules and it will be fine.