In a writeup on Read/Write Web Emre Sokullu asks if UI Innovations to Quintura Search Engine will be enough to get more users for Quintura - and the answer is no, except in some cases with Vertical Search Engines. 

"…Like Quintura, Snap relies heavily on UI innovations. The problem with relying on UI innovation is that the barrier to entry is too low. The big players Google (SearchMash) and Microsoft (Live) are actively experimenting with UI innovations.

However I think UI innovations will be very suitable for vertical search engines. For example flight search engine Kayak and job search engines like SimplyHired and Indeed can deliver UIs that take into account the unique requirements of their topic focus. Quintura Kids and Quintura's upcoming 'Search In Site' feature can also succeed by delivering UIs for niche audiences. However I don't think that up and comers like Quintura Web Search can easily convince us to change our general search attitudes. It'll take more than UI innovations to compete with Google. "

I think there's been a lot of work done on improving search engine interfaces, but it has not yield much, if any marketshare to any search engine that's tried.

I took a Read/WriteWeb Poll - here's the results (not a large number of people voted).

Thank you for voting!

Yes, the likes of Quintura provide a viable alternative to Google for general search 17% (9 votes)

Yes, but it won't be a single alt search engine - united they stand… 19% (10 votes)

No, the barrier to entry (for other startups and bigcos) with UI innovation is too low 31% (17 votes)

No, Google has it covered 33% (18 votes)

Total Votes: 54