The 3 GoPro HD Hero models are
HD hero
Known also as original, HD1 or Hero1 since the Hero2 camera out this is the 1080p hd hero model that does 1080p30 medium fov 127 and 720p60 wide 170 fov. It works with all the bacpac expansions battery, LCD, 3D and wifi. It does have limited use of the wifi bacpac as it will not do live streaming only and only work as a remote control.
HD Hero 960
This was a cheaper version of the original HD Hero above. Main difference is the highest video mode is 1280x960p30 and it doesn't do 60p in 720 which limited to only 720p30. This doesnt except any bacpacs at all as it has no expansion port.
HD Hero2
this is the current latest model which is an improvement over the HD hero commonly known as HD2 or hero2. This has improved image quality and selectable FOV modes in 1080p, this is also meant to be available in the 720p modes in a future firmware upgrade. There is also a Protune firmware upgrade in the works that will improve image quality much further with higher bit-rate encoding 35Mb/s from the current 15-20Mb/s along with a more raw style video output to make colour correcting and mixing with other cameras much easier. This excepts all current bacpacs and will support live streaming via wifi when the soon to be released app comes out. Wifi will not work underwater though so its only good for above water use.
Here is the camera comparison at the gopro site
http://gopro.com/product-comparison-hd-hero2-hd-hero-cameras/ All these models come with the same water proof housing with a round lens, this is unfortunately Blurry underwater even though its rated to 60m depth so you need either a 3rd party flat lens or the GoPro dive housing.
The cameras come in different packages such as Naked, Motorsports, Helmet, Surf or outdoor. These are all the same camera with the stock underwater housing with round lens, they just have different mount options in each package, you can buy any mounts separately so just get the package you think youd use most mount wise and if you want more you can purchase any other mounts later.
There will be a new model most likely called Hero3 which is in development but GoPro keeps things pretty quiet, they have made some hero2 announcements regarding the wifi bacpac app and protune that have been delayed and has received some negative feedback so I think they will go back to their old method of just keeping quiet and releasing it when its ready.
I think it will either be released this month along with many other brands at Photokina or otherwise most likely sometime in the next 6 months. Its been just about 12 months since the Hero2 got released and the Hero1 was around for a few years before the Hero2 came out. There were also some GoPro models before that which all had a similar look to them but these were just SD versions quite a few years back.
