1) I can never remember the "intuitive" keyboard combinations to do this on my mac, but I can remember "easyprintscreen"
2) Useful. I can capture my screen, draw on it, highlight issues or bugs or whatnot, and share it.
3) I know you'll keep it running because it has an obvious, lucrative business model (assuming you monitor what screens people capture for the occasional useful password, credit card numbers, stock tips, blackmailing opportunity, etc...)
This gave me quite a panic, please fix it or else someone else will make a bigger mistake.
To make it even more dead simple, you may even want to show a video. I'm not kidding.
There's definitely middle ground for quick annotation, without going crazzzyyyy. If you can screenshot, annotate, and upload in 5-8 seconds, you've got my $$.
I am not sure if there is a difference, if not maybe you can simplify the message :)
The only thing this seems to be is a picture paster with save to server function that can be linked to using a short url.
This is nice, as I rarely want to capture my whole screen.
As a precaution, I minimized everything. :)
I use a clipboard manager which is nice, and past copies are saved for a defined few hours or additional entries.