Let's face it. Google is search. When we first started developing plug-ins to our content management system, we did what any other software company would do and attempted pre-maturely optimize our solution to support any search engine. But pretty soon that gave way to Google specific reporting, optimizations, and API integration.
Google now has 2 menu items in the i-Dialogue control panel. One for API integration and one for Webmaster reports... and as we start rolling out a new daily email reporting system, Google once again has it's own specific reporting module.

Some reports show that half of all Internet searches were done through Google in 2007, but I suspect it's closer to 60%.
From a relationship marketing software perspective the trend is clear. Generic SEO and PPC tracking features will start giving way to Google and Yahoo specific tools and reports as this becomes a 2 horse race that controls 80% of the search advertising market combined (but that's not to say there won't be plenty of opportunities in the Long Tail).
So as a Microsoft partner, what are my thoughts on MSN and Live? www.live.com market share is truly disappointing and perhaps somewhat undeserved. The image search feature is much better than any other search I've used and I like the fact that Live Maps makes a guess at my Geo location based on my IP address and defaults to my location.
But I still find myself using Google for text, news, and Blog searches, simply because I know Google's algorithms set the industry standard and anything else has a feeling of "also ran" when you use it.
Finally, www.ask.com is another dark horse search engine that probably deserves more market share than it has today. It's quite a comeback story and you can really see the passion that went into reinventing this 90's Internet bubble darling.