"We’re all familiar with 80-20 problems, where the last 20% of the solution is 80% of the work. Search is a 90-10 problem. Today, we have a 90% solution: I could answer all of my unanswered Saturday questions, not ideally or easily, but I could get it done with today’s search tool. (If you’re curious, the answers are below.) However, that remaining 10% of the problem really represents 90% (in fact, more than 90%) of the work. Coming up with elegant, fitting and relevant solutions to meet the challenges of mobility, modes, media, personalization, location, socialization, and language will take decades."
The main advances necessary in search at the moment are listed in the article as being mobile, media, personalization and language. That does broadly cover it.
This made me smile though :
"So what's our straightforward definition of the ideal search engine? Your best friend with instant access to all the world’s facts and a photographic memory of everything you’ve seen and know."
I'm not sure about it being my best friend, I think if I did say my best friend was a search engine my non-geeky friends would have me down as a lost cause :)