Granted, this is not a professional attack on the problem, but there were a few VCs in the crowd and they were stunned at how nobody found any real new ideas to attack it at all and when asked about that, it revolved around data quality and data timeliness.
Data timeliness is a problem nobody seems to have solved. I keep seeing LinkedIn posts and FB posts and tweets that have dates in them and thus are no longer relevant as the deadline has passed, or will get the old version of something to come up on Google first.
New media, like Hoodline, breathlessly report on what you missed last week but will never pay a human to actually assemble a future events list.