This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
I have used this form of queries(i.e without select) while working with hibernate. In those cases it returns all entities mentioned in FROM clause. According to ejb3.0 spec both select and from clauses are mandatory. May be JBoss server support this form of queries as extra benefits. But such queries definitely will not be portable across application servers.