Though there appear to be a confusing array of cross-country binding choices, the boots you've selected will virtually make your binding choice for you. If you haven't been nordic skiing in a while, you may only be familiar with the older 3-pin binding system and duckbilled boots. Modern nordic boots are constructed with a single pin on a grooved sole that easily snaps into the binding and allows for a completely natural kick and glide motion. The 3-pin system is still used, however, but today's versions are paired with heavier, sturdier boots and wider skis for backcountry touring away from groomed trails. See the F.A.Q. on bindings if you'd like more in-depth information.
The best choice for Classic Track or Light Touring ski models. There are two competing designs out there, the SNS (Salomon Nordic System) and the NNN (New Nordic Norm); both operate almost identically, so you should choose the best-fitting boot and let it determine the binding system. Classic bindings come in higher performance race versions as well as casual touring models, with either an easy auto step-in or a more secure manual closure system.
Example: Rottefella Auto Tour
Possess stiffer flexors and an overall design suited to skating stability and control. Most skate bindings are operated by the manual system described above. Obviously paired with skis of the skating persuasion.
Example: Rottefella R3 Skate
There are two distinct choices here: The first is for either a SNS-Backcountry or a NNN-Backcountry binding, which use thicker rods and larger binding plates to allow stability on rough trails. For point-to-point touring, these bindings are the best, and they come in auto or manual entry versions that are easy to operate, just like their classic cousins above.
The second choice is to opt for a 75mm 3-pin system. These boot/binding combos are the most powerful and truly allow enough edge control for telemark or alpine-style turns. However, touring takes a little more effort in 75mm boots and the bindings can take some patience to get in and out of. Regardless of the system, Rugged Touring skis are the best match.
Examples: Rottefella Magnum BC and Rottefella Super Tele 3-Pin