Twitter is heaping ridicule on an online report from Realtor.com that gives the false impression that San Antonio is a suburb of Austin. The report, published Tuesday, analyzed national trends in home prices, comparing the current downturn in the real estate market to that of 2006. It correctly noted a recent price drop in San Antonio, but offered a questionable explanation of where the city is located — not to mention how big it is compared to Texas’ capital city.