The battery (the same one used for the Hero3) is accessed through the back panel, which is also where you'll find an input for use with GoPro's LCD Touch BacPac or Battery BacPac. The camera's left side has Micro-HDMI and Mini-USB ports and a microSDXC card slot that supports capacities up to 64GB. There is no 3.5mm audio-in for an external mic, but a Mini-USB-to-3.5mm-audio-in cable is available.
None of that differs from the Hero3 Silver, and the unit is still a little box that is comparitively delicate without its housing, unlike competitors from iON, Garmin, and Drift. The Hero3+ feels very well constructed and might survive a minor tumble, but it's GoPro's housing that keeps the camera dry and safe.
The waterproof housing that comes with the camera is good to depths of 131 feet (40 meters); the Hero3's dive housing was good to 197 feet (60 meters). If you don't need the camera to be dust- or waterproof and would like a bit more audio to reach the built-in mono mic, you can swap out the standard backdoor for the skeleton backdoor.
The housing is smaller and lighter than past versions and has a new lens surround, so if you've invested in any sort of lens filters or replacements for the Hero3 housing, they likely won't work with the Hero3+ housing. Also, the latching mechanism has been changed and now no longer has a locking switch on top. The housing is difficult to open, though, which is for the best in this case.
Not much else comes with the Silver Edition. Two adhesive mounts are included, one flat and one curved. The mounts work with GoPro's quick-release buckles that attach to the bottom of the camera's housing. You'll find a horizontal buckle as well as a vertical one, and also a three-way pivot arm so you can mount the camera on the top, front, or side of a helmet. A small locking plug (also included) can be used to help prevent the buckles from accidentally releasing from the mount via force or vibration.
There is no charger included for the camera, just a Mini-USB cable for charging via computer or USB wall adapter if you have one. GoPro offers a two-battery external charger, but again, you'll need a USB wall adapter or a computer to supply the power. Otherwise, since you're charging in-camera, you'll need to plan ahead if you want to carry additional batteries. You'll also need a microSD card up to 64GB for storage.
The camera can sit up on its own, but without an integrated tripod mount there's no way to easily attach the camera to anything without using a housing. Being the leader in action cams, there's no shortage of mounting options available from GoPro and third-party accessory makers. This is certainly an advantage to choosing a GoPro, but not a big one since other action cams either have tripod mounts or available adapters to use with GoPro mounts.
As for actually shooting with the camera, while you don't get the expansive list of recording options that you get with the Black Edition, you do get two that will be important to most users: 1080p at 60 frames per second and 720p at 120 frames per second. And, if you prefer tall HD, you get 960p at 60fps, too.
If you've never used a GoPro camera, navigating the menu system can be frustrating using its two buttons and tiny LCD. It's what I like least about GoPro's cameras in general. If you don't change settings much, it's not a big deal, and I'd rather have the option to change settings than not at all.
When you're done shooting and ready to edit, the free GoPro Studio 2.0 software for Windows and Mac is worth installing if you don't already have a favorite editing program. The latest version has drag-and-drop templates along with several other new features.
If you like GoPro's camera design and just want solid HD video as well as easier access to a large selection of accessories and mounts, the GoPro Hero3+ Silver Edition is the way to go. It's $100 less than the Black Edition that, while certainly better, may be overkill for your needs.