My friend Eric just sent me an IM to warn me that Google has now launched their coupon search functionality in Google Maps (via Mike Blumenthal’s blog). Some examples:

• restaurant in Buffalo, New York
• all coupons in San Francisco, CA
• all coupons in Toronto, Ontario, Canada

The search function is still buried but this might be the prelude of better exposure for that specific Google product. The Inside Google blog had recently discovered a bunch of coupon-related domain names registered to Google’s name.

What it means: coupons are a great way to track the efficiency of a local ad product as it brings clear traceability to the whole purchase process. Given their strong desire to track advertising ROI, I’m not surprised Google is interested in promoting this feature.