CQ5 doesn't work properly with JRE 1.7

I had upgraded my laptop, gleefully installed CQ5.5, and promptly was pulling tufts of hair out.

Custom Sling Servlets weren't behaving, and I was getting general issues with my CQ instance. What the dickens is going on?

Well... I had JRE 1.7 installed, not 1.6.14

http://dev.day.com/docs/en/cq/current/deploying/technical_requirements.html

Java Virtual Machines
CQ5 operates with the following versions of the Java Virtual Machine (Runtime Environment).

Platform	Support Level
Oracle JRE 1.7.x	A: Supported with CQ 5.5 SP2 or newer
Oracle JRE 1.6.x	A: Supported
Oracle JRE 1.5.x	D: Validated
Oracle JRE 1.4.2	Z: Not supported
IBM JRE 1.6	A: Supported
IBM JRE 1.5	D: Validated
HP JRE 1.5	E: Expected to work

So there are 2 options.
1. Upgrade to SP2
2. Downgrade the JRE to 1.6.14

After I had downgraded the JRE and restarted, things returned to normal again.

If someone upgrades to SP2 experiencing similar issues, please comment below.