Ask HN: Any startups applying for YC funding using the Google App Engine?

Blobstore really only exists to work around the lack of file access in AppEngine.

The pricing is something of an advantage, but don't choose it on that alone. If you know Java (or Python) already then it's worth using, but it's probably not going to give you enough of an advantage to switch platform.

The main problems are as follows: 1) Data privacy. Usually this is just people worrying unnecessarily, but sometimes there are legal requirements about where customer data is stored. These may be jurisdictional or geographic requirements.

2) Integration issues. Enterprise software is all about integration. The AppEngine integration story is getting better, but you'll need to understand the SAML based single-sign-on support that is built into Google Accounts and/or implement it yourself, and you'll need to become familiar with Secure Data Connector (http://code.google.com/securedataconnector/) to integrate with private data sources.