I've noticed that when my site is displayed in the map results it is no longer showing in the organic listings which means that I get only the map listing or the organic listing but never both.
The problem is that I'm getting 0.5% CTR on the map listing which to me is crappy.
I'm noticing in my analytics that Google Organic listings send me 77% of my traffic but Google Referral listings send me 1.1% and I'm assuming that the Referral means the map listing because I'm not using AdWords.
I don't think there is a way to find out how many impressions my site gets in the Organic listings so getting my CTR for a comparison would be tough.
But if they continue to push map listings over organic results I'm afraid of what it is going to do to my traffic from Google.
I don't think there is a way to find out how many impressions my site gets in the Organic listings
Webmaster Tools is one way (and the only way I know of) to get organic impressions rather than just clicks.
I was delighted when Google added that data, because I know from several patents that they monitor impressions for sudden spikes, and that can trigger a manual inspection and apparently slow improvement in rankings, as well as a possible penalty in some cases.
With regards to organic traffic, if it depends on query terms that are deemed location-sensitive, I don't think there's much a webmaster can do to fight the trend. Diversification of keywords and traffic sources is the best response, IMO.