Not terribly long ago I found myself on a dating site after a 5 year relationship. One of the first people to come up was my ex. With a compatibility rating in the high 90s. After blocking her I went on a series of dates with other ladies that the site had assessed a high rating, and every one of those dates was merely meh. Then a lady came along with a compatibility rating in the low 80s and we hit it off immediately and are now engaged!
Dan Ariely did some research on online dating and was able to prove succinctly that speed dating is a lot more effective at finding compatible people... and even more so, a social activity in which you must interact over a shared experience. The shared activity is actually a really strong indicator - the tests they ran basically had two people connected via text chat observing abstract shapes in speed dating rounds with no other information. If both partners of the conversation wanted to meet the other, they were introduced. Amazingly enough, this form of dating produced the most short-term dating prospects and the most longer-term relationships. FUN FACT: Both eHarmony and Match.com use Meyers-Briggs, but eHarmony goes for similarity while Match goes for opposites. Kinda shows that the whole algorithmic thing is kind of the wrong approach.