IMHO, building a solid product that people want to buy is more important than your exact domain name.
If you disagree with this philosophy and choose a marketing strategy that depends on getting a strategic domain, you should have your domain in hand early on -- before you announce the product, so everything you have to say about it points to the same URL.
Also, if you're willing to be flexible about renaming the product to match the available domains, you can circumvent the whole mess.