Toolbar/GonnaSearch is classified as a Toolbar.   Toolbars are Internet browser components that may operate under the guise of increased browser functionality.
The Fortinet Anti-Spyware Research Team is currently in the process of creating a detailed description for this Spyware.
For additional information about Toolbar, and how Fortinet classifies Spyware threats please see Fortinet's paper in PDF format:
Spyware Classification and Terms.