The system, from its left-hand side is pictured here. Starting at the left, there are the fan louvers (aka air intakes), a latched door that hides both a combo audio jack and a generic USB 2.0 port, and another built-in stereo speaker. The user-guide notes that a conventional microphone won't function in the combination jack.
Most of the system ports are mounted at the back. Ethernet is at the far left, followed by room for a SIM card (behind the sliding panel), a single USB 3.0 port, an HDMI connector, mini Display Port, combination eSATA/USB port, the power jack, and the Kensington lock. The combination eSATA/USB port is designated as 'Always On,' the manual defines this as: "By default, even if your computer is in sleep mode, the Always On USB connector still enables you to charge some devices, such as [an] iPod, iPhone, and Blackberry." The system can also be configured to charge devices even when in hibernation mode or when completely powered off.
There's nothing wrong with either control system per se, but users who aren't accustomed to a clickable trackpad may find themselves reaching up and clicking a physical button at the same time they click the trackpad, thus launching inadvertent programs or flipping context menus on and off. The various control systems could easily be explained by short tutorials or a configuration wizard, but either way it's not a huge deal--just something to be aware of.