When over the viewport, MOUSEWHEEL UP means Zoom-In.
(This is consistent with the 3D programs I know, Unity3D, browsers, Windows Explorer, and Adobe's applications.)
🙂
When over the timeline, MOUSEWHEEL UP means Zoom-out. It's weird.
🙁
I think the MOUSEWHEEL UP should mean Zoom-in for the timeline too.
(Sorry for bothering you with these minor things, Nate. I'd modify this myself if it were in hotkeys.txt. But it's not. Either way, I'd still have reported it though.)