I've been using Vim exclusively for about 2 years now, and I don't even want to begin to know what the hell is going on in that diagram. It was clearly not created for the purpose of teaching Vim but probably as an exercise of mapping out all the possible transitions between various modes and motions. Cool beans, but I hope the novices don't mistake it for something else.
If you're still on the edge about Vim, there have been a few good articles on how to begin learning it. What worked for me personally was learning the very basics, how to enter insert mode, how to save and quit, and starting to use Vim as a regular mode-less editor while slowly learning about various useful things you can do in normal mode ("hey, I can delete a word or a line with two key presses"). That way you can begin to extract use out of it immediately while growing increasingly efficient with other modes.
If you're on a Mac, MacVim gives you native OS X shortcuts for things like Copy/Paste, and maps selecting text with the mouse to visual mode which, combined with using insert mode, gives you the same functionality as a regular mode less editor would.
If you're still on the edge about Vim, there have been a few good articles on how to begin learning it. What worked for me personally was learning the very basics, how to enter insert mode, how to save and quit, and starting to use Vim as a regular mode-less editor while slowly learning about various useful things you can do in normal mode ("hey, I can delete a word or a line with two key presses"). That way you can begin to extract use out of it immediately while growing increasingly efficient with other modes.
If you're on a Mac, MacVim gives you native OS X shortcuts for things like Copy/Paste, and maps selecting text with the mouse to visual mode which, combined with using insert mode, gives you the same functionality as a regular mode less editor would.