FWIW, the Google products that are subject to the deprecation policy [1] will give a year's heads-up before they are shut down.
We aren't doing our job well enough if you can't easily transition off Cloud Platform (at least for the components that have obvious competitors... something like BigQuery is necessarily less simple). You should stick with us because you believe in the product, not some sort of lock-in, so you should find it easy to leave within that year.
As for whether that deprecation is likely, it would require a sea change. In the Wired article that came out yesterday [2], the quote is '“We will spend the majority of our development efforts on this New World,” wrote Hölzle.' And this is true, Google really is throwing Technical Infrastructure behind Cloud Platform. That's not to say Cloud Platform going away can't or won't happen, but I feel confident in my job sticking around.
[1] https://developers.google.com/cloud/terms/deprecation [2] http://www.wired.com/wiredenterprise/2014/03/urs-google-stor...