Overture with extension isn't the be all and end all. Good seo can make you thousands a month. Ask those who promoted crazy frog or any other product and managed to keep their domains in the top five in various engines, they made tens of thousands of pounds either in a month or in months.
I don't like the word generic either, is it an american term? I understand the definiton but somehow it doesn't fit. The word you want in the UK is keyword, that's all that matters, keywords. And as the term 'search engine' goes and it already coming with 70,000 searches it's got the possibility of making the owner with the right seo, thousands of pounds a month and that's the beginning. You can make thousands with just 10000 searches beforehand.
The possibilities are endless, Edwin I'm sure, knows what he's doing. It won't be easy getting atop 330,000,000 or 119 million results but it can be done. Quite rightly, when buying a domain name for a product or field, you want the most popularity with the least amount to jump in the engines so as search engine goes, it's quite a task but doable.
For ideas on domain possibilities just enter the keyword and with the plural and you'll get an idea at how valuable 70,000 searches before you even start to promote can earn you thousands. And if a buyer has the same idea...