After a successful uploads, by default, ScreenToss will copy its public link to your clipboard and notify you via Notification Center and a sound.
The following settings are available in Preferences ▸ General:
Downscale Retina screen shots: ScreenToss will reduce the size of screen shots taken from a Retina display by 50%.
Link directly to file (for embedding): Both Dropbox and Imgur share uploads embedded on a web site. Check this setting if you need to link directly to the file, instead (which is common for when you need to embed a file).
You can also automatically move screen shots to the Trash (or another location) after successful uploads.