First, let me state that I love the new image uploader. I can now paste screenshots with CTRL-G, Enter, type the first letters of my image, arrow keys to adjust, Enter to exit the dialog, Tab to the "Upload" button, and hit Enter one last time* to upload a screenshot.
However, it's still a new feature. The appearance varies widely between browsers, but I'm OK with that. It's native, it works well, and I'm happy enough. However, it's got some new-feature bugs (all based on OS X 10.6):
Firefox shows the full path to the image, which seems like security vulnerability (if typing in this box is a vulnerability, then showing the path is too, right? and hinders the usefulness of the dialog because you can't see the filename even just three folders down:
Also, the highlighting around the selected "Upload" and "Cancel" buttons is faint (look at the above screenshot) and the highlighting around the "from my computer" and "from the web" buttons is nonexistent:
More important than a lack of focus is the lack of interaction: Pressing Space or Enter doesn't toggle between the computer and web buttons.
Chrome doesn't highlight the "Upload" or "Cancel" buttons on electronics.stackexchange.com (Note: It works here on Meta, maybe we're just not on the most recent build yet?)
This is surprising, because it does show very nice highlights around the "From my computer" and "From the web" buttons:
...much nicer highlights than Firefox's one-pixel dotted line. Squint and you'll see it around the "Upload" button in the Firefox full-path image.
This browser has weird tab behavior: The "Browse" button is properly focused after hitting CTRL-G, so the initial action works. However, a Tab brings focus to Safari's URL bar, Safari's search box, the site search box, question title, question body, question tags, and then some unknown element which doesn't react, then back to the URL bar. You can't Tab away and then Shift-Tab focus back to the "Browse" button, and focus doesn't come back to the "Upload" button when you return from the dialog. Tabbing is just completely broken. Here's what it looks like after clicking "Tab" once:
I understand it's new, that these are minor issues, and that these are browser-dependent issues, but I'm just trying to help feel out the bugs in our new, shiny uploader!