The world of search engine optimization (SEO) was watching closely this Wednesday as Yahoo filed documents with the Securities and Exchange Commission saying that the deal to merge their search technologies with those of Microsoft would be delayed.

The partial merger between the two online giants has been public knowledge since July 29, and the deadline for the finalization of the deal was said to be this week. However, Yahoo’s decision to refrain from signing on startled many in the search marketing and search engine optimization (SEO) industry, who for months had been looking forward to the consolidation.

Yahoo said in the SEC filing that "[t]he parties are working diligently on finalizing the agreements, have made good progress to date, and have agreed to execute the agreements as expeditiously as possible." No new deadline has been revealed, but Microsoft said in a joint statement that "[b]oth companies are optimistic that we will be able to close this deal by early 2010."

The full details of how Yahoo and Microsoft’s respective search products would be reorganized are not yet known, but search engine optimization (SEO) experts say that there are likely to be numerous shifts in the SEO landscape.