John Gruber, in his overall write-up on the new C&P functionality on the iPhone, summarizes Apple’s philosophy when it comes to releasing these types of features:

That we had to wait two years for the iPhone’s text selection and pasteboard is a good example of one aspect of the Apple way: better nothing at all than something less than great. That’s not to say Apple never releases anything less than great, but they try not to. This is contrary to the philosophy of most other tech companies — and diametrically opposed to the philosophy of Microsoft. And it is very much what drives some people crazy about Apple — it’s simply incomprehensible to some people that it might be better to have no text selection/pasteboard implementation while waiting for a great one than to have a poor implementation in the interim.

I tend to agree with the Apple stance. Don’t let perfection be the enemy of the great, but do let greatness be the enemy of the good/fair/poor.