...beware the maximum viable product. Ease of adoption, clarity of the value proposition and lots of feedback far outweigh the risk of people saying "Is this it?" IMHO. Don't be afraid. There is nothing like seeing your product out in the wild. Go for it.
The key point is nothing new, but worth repeating: launch early and iterate once you have customer feedback. No matter how convinced you might be that you know that your product is worthwhile, without feedback from real customers you are steering your ship with neither compass nor map.
Roger makes another point which I don't quite agree with:
Leaving aside the enterprise (which I believe has a fundamentally higher bar for release than consumer), the biggest mistake I've seen has been to delay getting a product out in the wild and over-engineering it in the lab.
Enterprise products are no different. If anything, customer feedback can be obtained even sooner in the enterprise world, by pitching a product which has not been built at all yet, and trying to obtain letters of intent or even conditional purchase orders.
If you can't sell the promise, you most likely won't be able to sell the product either.
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