The vertical search wave is just beginning. Don't take my word for it. Take the word of the 50 or so people that raised their hands last night when asked by SDForum Search Sig event co-organizer Jeff Clavier whether they were in the process of building a vertical search engine.

Now, 50 smart engineers and business people would represent a decent number if it represented everyone in Silicon Valley working on their own vertical search project. But, those were the 50 people out of the approximate 175 that attended the vertical search engine focused event held at the Microsoft Silicon Valley campus last night. It doesn't include the oodles of others out there working on this segment that weren't there last night or don't even reside in Silicon Valley. After Dan Farber, vice president of editorial at CNET Networks, interviewed search engine expert John Battelle, there was a panel discussion that included representatives from SimplyHired, Trulia, Truveo and Healthline.

One thing that struck me was that real estate-focused Trulia and employment-focused SimplyHired effectively admitted that search technology itself is becoming commoditized and that some of their main differentiators are in the process of sorting that data, the user interfaces and business partnerships. That strategy has major ramifications for vertical search aspirants because it lowers the barriers to entry. It also begs the question whether the employment and real estate verticals will become commoditized just as the travel vertical search engine market has become. If you do the identical flight search on Kayak, Mobissimo and Sidestep, the results are very similar. Video search company Truveo claims its search process is fundamentally different from the normal crawling activity. And health information-focused Healthline claims its developed an ontology consisting of 850,000 keywords specific to the healthcare industry that enables it to provide better search results. I buy that. I also buy the fact that SimplyHired and Trulia can thrive despite commoditized results and inevitable competition from Google. That's because some people will want to go straight to a Web site to buy something. Others will prefer to visit a search engine such as Yahoo. And still others, will want to do their comparison shopping at their favorite vertical search engine. The success of many of these companies will depend on how many of those people out there fall into the latter category. —Joshua Jaffe