One of my best Firefox extentions is “SEO for Firefox” from SEOTool.com.  For any site you visit, the toolbar shows you information about that site’s inbound links and search engine rankings.  For example, when I visit the South by Southwest website, the toolbar displays that the sxsw.com has a google pagerank of 7.  It also shows me that there are 74,000 inbound links to the sxsw.com and 473,000 links to pages under this domain.  Why would the average web browser care about this information? Read on!

Originally, I installed this plugin to help me learn more about SEO (search engine optimization).  But it’s been useful in a way I wouldn’t have predicted: knowing the number of inbound links helps me quickly make decisions based on popularity.  It helps separate the signal from the noise.
Let’s say you need an online bookkeeping solution.  You ask friends for a recommendation but get none.  So you google “online bookkeeping solution”.  The results are overwhelming and confusing.  You poke around a bit more and stumble on a Techcrunch article that mentions a bunch: Outright.com, Xero.com, Saasu.com, Lessaccounting.com, Fastdue.com.  How do you decide between them?

You’re a busy person. You don’t want to spend the entire day researching and reading reviews.  You need to pick one quickly and get on your way!  You visit each site and keep an eye on the SEO toolbar which instantly shows you the inbound links for each of the sites:

Outright.com: 2,000 inbound links
Xero.com: 11,000
Saasu.com: 2,000
Lessaccounting.com: 2,000
Fastdue.com: 284

You quickly identify that Xero.com has the most inbound links.  It’s probably the most popular because it’s the best product (this point is discussed in more detail later).  Maybe you do a quick twitter search to double check that people are in fact saying good things about the site.  Everything looks fine.   You sign up.  Decision = done.

Inbound link information is also extremely helpful for figuring out roughly how different competitors size up against each other.  Camelbak versus Nalgene? 31k links versus 6k.   Turbotax vs TaxAct?  340k vs 8k.  Google.com vs Live.com vs Ask.com?  515M vs 66M vs 9M.  Trying to figure out if anyone else has heard of some (seemingly obscure) website/startup that a friend has told you to check out?  Drop.io perhaps?  110k inbound links — “whoaaa, well ok then, I guess drop.io is worth taking a look…”

On a similar note, this information can help you avoid scams and phishing attempts.  If for some godforsaken reason you should land on http://www.ie-internet-explorer.com/landing/ie/ie-internet-explorer-browser.php or http://msie.com, the toolbar shows that these sites both have a total of THREE inbound links.  Obviously, if they were legitimate sites owned by Microsoft they would have a few more links — so you should probably stay away from them.

Quickly assessing the legitimacy of a site is especially important if you arrive via an advertisement.  Anyone can throw up a seemingly legitimate looking website and buy search/banner ads to drive traffic there.  But getting a few thousand links?  That’s a much harder task.

Having information about inbound links at my fingertips help me separate the wheat from the chaff and figure out what’s worthy of my attention and my time and perhaps my credit card number.  It’s basically a lifehack.

Using Popularity to Judge Quality
The decision making process I described above uses popularity as a proxy for measuring quality.  In most cases, popularity is a suitable enough measure for quality, especially when a decision needs to made quickly.  After all, “nobody ever got fired for buying IBM.” This method of decision making does however discourages you from trying anything other than the market leader.  What if second place truly does “try harder” in an Avis sort of way?  What if this method causes you to miss some awesome new website or company that hasn’t received a lot of attention and inbound links yet?

Another issue is that this method reinforces a lock-in situation where the rich get richer.  But Google itself is guilty of this too: the results of the search engine page are largely dependent on inbound links.  More people find the sites with more inbound links.  And then they link to these same sites which leads to a self-reinforcing situation where only the top ranking pages get found — a phenomenon which has been labeled Googlearchy.  (also see the original academic paper that invented that concept/name [pdf])

The truth is that popularity is always used as a filter.  People watch the NYTimes Best-Seller list like a hawk to figure out what to read.  The iPhone Top 25 App list is the key to getting your app noticed — and downloaded.  And popularity is frequently a selling point: automobile companies brag about their “bestselling” models.  Why?  Somehow it’s comforting to know that you’re not alone in your decision to purchase this particular car.  Millions of other people have done it.  They can’t all be morons, right? right?

(P.S.  This is where the sociologists come in.  If you’re interested in this topic — popularity as a decision-making tool — read some of the research of Duncan Watts, a former sociology professor of mine at Columbia.  He has one particularly interesting experiment where researchers tweak how ‘popular’ different songs are in an fake online music store and test the relationship between preceived quality and stated popularity.  Full research paper is here: Experimental study of inequality and unpredictability in an artificial cultural market [pdf])