I switched from AltaVista because Google.com was faster and less full of spam. I still think that is the case compared to other search engines for common searches.

That being said, more and more searches are using ever increasing numbers of search term words, and that can get spammy.

Google make no secret of investing in search and the presence here of Matt Cutts is testament to the fact that we(?) are listening, with very frequent algorithmic tweaks and responses.

I don't feel it's useful comparing Facebook's "like" system with a search engine. Whilst it is useful to know what friends think of things, this can also be gamed by smart marketers.

I don't think it sucks - but there are use cases and perhaps for certain users where the experience indeed sucks. I for one have been using the 'spam flag' extension for Chrome and feel that something can be done with the results. Perhaps this will help?

(my opinions are my own and not necessarily that of my employer).