happymurtad, I know you said outside of salafi circles, but with the real life implications is there really a difference in practical terms? Their world views seem so similar, and at times it really is hard to tell one from the other in the 21st century. They seem to repeat what the other says.
From your perspective you probably would not see much difference. In the broadest sense, anyone can really use the word "salafi" if they want to. It's like putting "The Real" in front of your group's name. Issues of methodology that are disagreed upon among groups calling themselves salafi probably would not mean much to you. There are some really abstract disagreements that divide them, though you'll likely only see a bunch of beards.

The term "wahhabi" by definition shows a link to a Saudi brand of salafism. It is not a label that any of the groups would use themselves.
I think the biggest differences that you would notice would be between salafis and salafi jihadis.
Salafis, for the most part, view "obedience to those in authority" to be a key part of faith. Government overthrows or protesting against a government that claims Islam is not allowed to them. There are all sorts of textual proofs for this position that I won't get into right now. These types of salafis will be seen throwing their support behind regimes like the Saudi regime, the gulf monarchies, and even the North African governments. They will be ultra-conservative and mostly literal (what they would call orthodox) in their interpretations of scripture.
Salafi-Jihadists, on the other hand, will - in addition to the conservatism and literal interpretations - also advocate jihad against any government that does not rule by sharia. ISIS would be an example of this.