From: Near Portland, OR
For one thing there aren't that many people paying attention to this forum anymore.
At their core, they are much the same, but AE is richer in just about every way. The modeling of reality is more accurate, the player has more control over various things, many bugs in the original game were fixed, and a lot of things were made faster.
Because there are more controls and features, AE is a bit tougher to learn, but more rewarding once you do. The forum is very supportive answering questions.
WitP AE - Test team lead, programmer