Nyagoslav notified me of a bug with Google Places areas served feature.
In short, when you try to update your Google Places business profile to include specific areas that your business serves, it does not reflect the change.
Several complaint threads can be found at the Google Places Help thread. One user said:
The topic of this discussion is Service Areas and Location Settings. I tried to click on Yes, this business serves customers at their locations and I am able to do all of those features but when I submit the changes and then go back in to check on them, it shows that my listing is set at No, all customers come to the business location. Is anyone else having this issue?

Google has not confirmed the issue and there is no ETA for a fix.

Comments:
Megan
09/20/2011 08:21 pm
I have tried to update many clients today and it is not working.
Aussiewebmaster
09/20/2011 11:07 pm
guess we can ask at the Google Places event on Thursday
Leeson86
09/27/2011 04:33 pm
Still not working for me. Going on about ten days now. My listing is invisible as well. It does not appear unless I select " this business serves customers at their location", which I can not edit. Awesome.
Junkernator
04/17/2012 06:27 pm
Not working for one of my clients either.