As I go through the process of getting familiar with Google AppEngine, I'll post interesting things I learn (mostly so I can find them later). Here's a quick note on GQL query syntax:

Assuming a model called Customer, you can use:

1) customers = db.GqlQuery("SELECT * FROM Customer ORDER BY name LIMIT 10")

2) And since GQL queries always return data objects, you can skip the SELECT * and abbreviate to:

customers = Customer.gql("ORDER BY name LIMIT 10")

3) You can also use parameters like this:

customers = Customer.gql("WHERE name = :1 ORDER BY name LIMIT 10", "Smith")

4) And finally, #3 with named parameters like this:

customers = Customer.gql("WHERE name= :person ORDER BY name LIMIT 10", person="Smith")