What feature is causing these code hints to appear in VS2010?

Question

This "feature" seems to have randomly appeared in my Visual Studio 2010 functionality. I have a year-old build of ReSharper, and VSCommands Lite installed, but haven't changed any of my editor settings recently. I installed the Achievements add-in recently, but that seems unlikely to have enabled this feature. Where did this come from? I'd like to show coworkers how to enable it, but can't figure out where, how, or why this magical new feature now appears in my editor.

The feature shows faint grey statements that echo the opening brace of a statement that's no longer visible beyond the scrollable window off of the screen. For example:

Answer 1

Turns out the new functionality is part of VSCommands Lite, which auto-updated itself recently (the latest version was released a few weeks ago). The update added and enabled this new "Code block tagger" feature.