I could have written this script myself... but it probably wouldn't have integrated as nicely into the reader UI if I had done it. This a very nice, clean, and simple script. It works exactly how it should. The code is also laid out very cleanly, which allowed me to make changes, mostly related to using is.gd for short URLs instead of TinyURL.
author: you might want to consider using is.gd for short URLs instead of TinyURL... the URLs are several characters shorter and the API is simpler (no regexing the response page from tinyurl, is.gd returns nothing but the URL if you use their API). I can provide my changes if you want, but obviously looking at your code I'm sure you could figure it out.
I love this script, It really helped me organize my google reader and twitter account whilst still allowing me to play Temple Run Online
This script does work great, it adds a link to post the item to twitter just as advertised. It integrates well, however this functionality already exists in Google Reader by default.
If you go to settings and "send to" you can add twitter,facebook,digg,reddit and many others to Google Reader allowing this functionaltiy but for even more services all in a neat dropdown menu.
So while this script works great it really isn't worth using when "send to" Google Reader's default social feature, works much better.