They also noted that 76% of this traffic comes in as referrals from other search engines.
This is slightly ironic, since Jason Calacanis, founder of Mahalo, has historically been very critical of the worth of search engine optimization. I’m not the only one who sees the irony in this, since Allen Stern also noted it, saying “Mahalo is an SEO Play “. As Allen notes, if Mahalo didn’t want this traffic it would be easy for them to block the spiders thru their robots.txt file.
I’ll go further: it appears to me that Mahalo was built with optimization in mind from the outset, since it was built with a clear navigation structure and non-query-stringed, keyworded links — something that rarely occurs without site designers intentionally desiring to bring in search spiders.
The unfortunate side of this is that Mahalo appears very vulnerable to me now, since they’ve designed themselves in direct opposition to Google’s Webmaster guidelines. Mahalo has marketed themselves as “a human powered search engine”, and Google’s guidelines state  that they don’t want to be indexing search results pages:
“Use robots.txt to prevent crawling of search results pages or other auto-generated pages that don’t add much value for users coming from search engines.”
I’ve seen Google drop search results pages from large sites due to this very thing before, and Mahalo is now prone to receive this same treatment. It’s a bit sad in a way, because startups like this need traffic to be successful, and Mahalo’s recent traffic growth is in danger of getting completely reversed if Google now chooses to apply their editorial controls as they have done with others.
Mahalo appears to have around 145,000 pages indexed in Google at the moment, and I’d say they are in danger of losing most of that indexation.
Of course, Google’s definition of what constitutes “search results pages” may be a bit semantic at times. There are many catalogs, guides and directory sites which expose their “search results pages” for indexing, and Google appears to accept those as good quality content sites.
It’s not always clear what definition Google is using for “search results pages”. It may be that they’re wanting to reduce/prevent the indexing of “search results pages” which are merely other indices of webpage links under the concept that Google SERPs are already a sort of meta-content, and indexing other similar meta-content is of fairly low value to endusers. In this case, Mahalo’s traffic certainly is endangered, regardless of the fact that their results pages are human-generated as opposed to the more traditional, algorithmically-generated variety. A rose is a rose and search results are search results.
Jason might want to bite the bullet and consult with some SEO experts now to get recommendations on how to offset the risk of losing his newly-found traffic. He’s one SEO misstep away from taking a bump on the nose.