1. Siri gets data from Yelp, so make sure you have a complete listing: Get a Yelp Business Listing
2. TripAdvisor is another source for Siri: Get a business listing on TripAdvisor
3. Siri pulls data from over 60 sources, submit your listing to Localeze. You will need to pay for your localeze listing, but it will save you hours of time submitting to each directory individually. I would however, take the time to list yourself in Google Places and claim your listing with Bing.
4. Optimize your website for long tail keywords. Give people an opportunity to chat and they can become quite verbose. People use all kinds of combinations of words, it is a best practice whether people are searching via Siri or their desktops.
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