Any known Bugs? Yeah, the mimetyp isnt read out properly atm, will fix that in the next version.
Where are the files? The files are in the wp-picturehoster directory in the wp-content folder
Where can I find the files in WordPress? You can have a look in the mediapool in the WordPress backend.
Are there any template functions? Yes, there is a function 'wpp_picturehoster()' which is basicly the same as the shortcode.
What will be the next version? I plan to do an extra management page beside the normal mediapool. Also there gonna be a plugin page with some settings, i.e. expiration date and so on.
props to yves for the idea to write such a plugin, well actually he want it and I did it ;-)