[seesharp]

I can recommend using Imgur for storing screenshots. For Windows you can use Greenshot (http://sourceforge.net/projects/greenshot/) and for OS X you can use Mac2Imgur (https://github.com/mileswd/mac2imgur).

Uploading images is instant, the image quality is higher, embedding is actually possible, you don't need to have an account and thumbnails are automatically generated.

[cheald]

This has been my solution, too. It's much faster than Dropbox.