For Americans who are tempted: check out the DAFT program (Dutch-American Friendship Treaty), which gives entrepreneurs a two-year visa, renewable for another two years. It was relatively painless.
As for the Dutch speaking — it's not necessary in Amsterdam, as everybody speaks English. But I am indeed making an effort to learn the language. In fact, it's a bit frustrating to practice, as everybody just speaks English to me. This is a common problem with non-Dutch-speaking expats here.
There is a wee cafe on the Singel which does BLTs which are so good, that it the only food that i care about, everything else is mere mass. These BLTs though...
Yes, I'd move for the BLT alone!
PS: Food-wide, there are many local shops of high quality depending on your preferences. I can highly recommend Maoz falafel although there are also less well known shops selling good falafel. The salad bar has unlimited refills. Although the stores are so crowded/popular I never end up going to refill more than once.
Downsides: Expensive, I can't speak Dutch.