I think this might be my favorite chart ever.
This is the Google Insights graph comparing the use of the search term "apartments" vs the search term "real estate" in the Chicago Metro area over the past two years. While it will update over time, what I want you to look at is the divider between 2010 and 2011. Do you see what happened? Apartments completely overtook real estate and never looked back. (If you're reading the archives in 2013 or later and you can't see that date anymore, drop me a comment and I'll update the chart.
Do I need to explain further? I think not, but let me know in the comments if you don't get it.