I ran across this, and haven't seen this mentioned so far. Adding fanshots is now way easier than it used to be. If you go to the main fanshot page (linked in the title), on the upper right is a "+Fanshots" icon. Drag that to your bookmark toolbar at the top to make a bookmark.
From that point on, when you're surfing the net, visiting youtube, viewing a picture, an article on ESPN, or whatever, and you want to turn that into a fanshot, just click that bookmark, and it will open up a new window, populated with all the info about that image or video, ready to post as a Fanshot (you can add additional comments too)
Amazon has the same feature for adding stuff to your wishlist, when visiting other sites. It's been handy as well. Take a look.