Yesterday it was announced that Yahoo and Microsoft reached a deal that could give Microsoft almost 30 percent of the search engine market, and according to at least one expert, this will change the search engine optimization (SEO) landscape.

While the deal still has to meet approval and will likely take some time before Microsoft is handling all of Yahoo’s searches, SEOmoz’s Rand Fishkin says the deal will have some positive and negative effects on both Yahoo and Microsoft in regards to search engine optimization (SEO).

For one thing, businesses should put at least some effort into search engine optimization (SEO) for Microsoft’s Bing as it is likely to have at least a 15 percent share of the search engine market, according to Fishkin.

Fishkin writes that implementing a search engine optimization (SEO) strategy for Bing would be a good idea because of the increased "richness" of its results.

"Bing’s results are, by default, ‘richer’ than those of Yahoo and Google. Although Yahoo will be controlling the user interface on their end, it’s likely much of that ‘richness’ will make its way into the Bing results inside Yahoo," he wrote. "Bing also surfaces only the top five results for many queries, meaning a higher concentration of clicks on those top results."

Although Microsoft and Yahoo say they expect the deal to be completed early next year, there still may be some hurdles the companies need to pass as many in the industry expect the Department of Justice to take a hard look at the agreement.