It could be that when the data was entered into the MLS that your agent/broker forgot to check the box for "syndication". The Austin MLS changed over to a new software vendor, and by mistake, this box was set to default to unchecked and many agents/brokers overlooked the issue. They have since fixed the problem, but listings entered a while ago are still sitting with the syndication box unchecked, if they were entered into the MLS prior to the fix.
If the syndication box is checked, Trulia, Zillow, and some other sites that pull data from syndication, will update within 6 to 72 hours, depending on their business practices. Your agent/broker can go in and see if the box is unchecked, and fix the issue.
I've found Trulia and Zillow both seem to pull syndicated listings from the source after about 6 hours, but some other sites can take much longer. Realtor.com, and all other agent/brokers sites in Austin, pull through a different feed, call IDX. You can check if IDX is turned on for your listing by going to another brokers website and searching for your listing there. Try http://www.realtyaustin.com
and see what shows up!
Check your pictures too. This is the biggest draw to the public, make sure they are high quality professional photos that show your home in the best possible way. If you don't interest people with visual appeal, they'll never come look at your home.
Hope this helps.
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