Sure, i'll give a little feedback, don't use flickr though, so not actually testing the plugin(just looking at the code)
Quick way to examine the code is view the plugin's main file here(fyi for anyone else who wants to look at code without needing to download).
http://svn.wp-plugins.org/hey-its-a-flickr-widget/trunk/heyitsflickr.php
Here's my critique based on a quick scan over the code.
- If you're going to re-register jQuery, you should make it optional for your users.
- You have 3 filters using the same name but passing along different data, perhaps you copied them but forgot to give them unique names?
- Make your plugin translation ready, just adding
__() and _e() throughout the code isn't enough, perhaps my blog here will be of use in helping getting your plugin translation ready.
- Place any and all text, ie. written text, inside translation functions, so the plugin can be translated completely.
The blog post i linked to has a very basic example plugin that shows you how to make your plugin translation ready, if you prefer to just learn by looking at code, here's a direct link to the example plugin.
Hope that's helpful.. :)