Well.. its not so much the vaporware aspect of things... Succeeding in search today is all about scaling. Only the big three have what it takes to build huge data centers. A startup the size of powerset -- not really. Natural language search is something that the average search engine user would consider a "cool feature" at best. The real power of a search engine comes from its ability to cater to the long tail -- which translates to its ability to build huge data centers.