What are the hardware differences between the Xbox 360 slim and the Xbox 360 E?

The 360S(lim) and 360E are fairly similar, with some slight differences:

• The S has 5 USB ports, where the E has 4.
• The S was the last model to feature the "AV Connector". The E drops this port in favor of a separate HDMI port and composite (ugh) out port. Optical audio appears to be missing.
• The case design has been updated to match the design of the Xbox One.
• The hard drive is slightly easier to remove, although it is still only replaceable with official Microsoft replacements.

Notable elements kept constant:

• Price & configurations. The E was introduced at the same price as the S.
• Fans & optical drive design. This means the E likely has the same noise profile as the S.
• Architecture. It's the same chips, same amount of flash, RAM, etc. Halo won't run any faster on it ;)