Google Search by Postcode

When searching for "mattresses" on Google, I noticed this for the first time ever this morning:

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For this particular term, both when logged into a Google Account and when searching while logged out, Google is asking me if I want to refine my search further by postcode, and giving me the option to save the setting.

Searching for "beds" however, gives the generic result.

This may be the next step in providing tailored listings, making use of Google Local within the main search results for very generic keywords.