I too had the exact same problems as the “Whither PlayServices” thread - and the fix in 4.1.2 worked for me.
I was getting the failure to find the Play Services in the log, as well as possible incorrrect API key - the app did not fault out it just did not display a map - only white space. I deleted the updates to play services via app manager, allowed it to update when Hangouts wanted it, deleted my app and reinstalled it and Voila it worked.
However I should note that even when it is working and properly displays a map I see the “Google Play Services resources could not be found” msg in the log and they are indeed present. I have made all the requisite manifest mods etc, so I am not sure what this msg is referring to.
What this chapter demonstrates is how freaking HARD it is to actually understand why ANYTHING works EVER in Android. I have had the pleasure of using their maps API in years past via PHP and it was quite straightforward - this is PAINFUL.