Windows 7 had an old implimentation of Pinch to Zoom where bringing your fingers apart/together would act similar to ctrl + +/-, the standard zoom. It's not as nice as granular zoom (like iOS/Android use) but it worked. Most notably it doesn't work in Chrome (did before) but I haven't noticed it working in any other apps. In windows 8 desktop mode, pinch to zoom doesn't seem to work at all. It doesn't even work in One Note 2010, which, if I recall correctly, had granular zoom in Windows 7.
I have an (older) 2 touch point multi-touch monitor, and I can see the visual feedback that the two touch points and coming closer/farther apart, but it doesn't zoom. Note I'm using the touchscreen, not a touchpad or the Arch mouse or other peripherals.
Can I enable this somehow or is it gone from Desktop mode? It works fine in Metro apps. Additionally I get weird visual feedback when placing my second finger on the screen; a shrinking transparent square appears somewhere between the two fingers, visually similar to the Right Click visual queue when long-pressing. It's not a right click though, I can't tell what, if anything, it's doing.
