I was going to say...the Neons wouldn't nip the angels, but the angels might nip (or completely eat) the neons. I've heard on this site that neon tetras constitute part of angelfish's natural diet, and so you've got to excercise extreme caution if you're going to mix the two.
One strategy I've heard of is to have the neons in FIRST, and allow them to grow pretty large. Then, add a young angel, so that the neons are already established in the tank and are too big for the angel to eat. The angel, in theory, will get used to the neons as tankmates rather than food.
If you add neons after adding an angel, the neons would probably be so disoriented when they're placed in the tank that the angel would have an easy meal.