What's interesting to me is that there are still hard limits for billing-enabled apps. There's the respectable ones: You get the full use of a 100 megabit pipe

What's interesting to me is that there are still hard limits for billing-enabled apps. There's the respectable ones: You get the full use of a 100 megabit pipe, 72 CPUs, and a 500 req/s proxy; plus you can send millions of emails a day. On the other hand, the limits on datastore and memcache access are out of proportion to the bandwidth and request limits, especially when compared to the free limits. With a paid app you're unlikely to be able to ever hit the Bandwidth / CPU / Request limits because you'll be starved for data, whereas with a free app the opposite is true.