Why should I choose BerkeleyDB JE v6 over v5?

the Oracle BDB release notes are unfortunately meatless.

Why do I need to switch from BDB JE version 5 to version 6? Does it have a significant performance improvement? Because if not, I can only see these two minuses:

• v5 uses Sleepycat, v6 uses AGPL 3. So v5 is GPL v2 + compliant whereas v6 requires me to go to GPL v3
• v5 works with Java 6, v6 requires Java 7