Visual methodology = visual language + rules of thumb
For example, bCisive Online comes with the following set of boxes, which together making up its out-of-the-box visual language:
This set descends from the non-visual Issue-based information systems (IBIS) methodology, and is suitable for activities including Dialogue mapping when working in a group or facilitating a meeting, and Issue mapping when working solo.
A map using the default visual language
An example of another visual language / methodology is the set of boxes and templates that we designed for use with bSelling, based loosely on the non-visual Solution Selling methodology (and simplified a good deal):
This set is designed to help a salesperson understand the needs (pain points) of a prospective client, the cause of the pain, who else is affected, and what capabilities would help address each pain. Here's an example of how visual thinking using this visual language can help lay out a picture of the prospect:
Diagnosing Customer pain with the bSelling visual language (click to enlarge)
So different visual languages work better for different purposes.
Rationale is mainly built around a visual language for argument mapping; bCisive has several; with bCisive Online we plan to offer the possibility of organization-tailored visual languages plus templates.