In addition to what lighton proposed awhile back, would it also help to implement the same error message for "pending request" and shows that already exist here at next-episode.net? For example, if I request "Show XYZ," but someone else also requested the same show right before me, I should see the following error box. This should be filtered against the existing added list.

I also see a lot of shows that are rejected because they already exist. So maybe the same can apply when someone tries to request a show that already exists...

The only questions I have are, would it be easier to filter this against the "Show Name" typed in the request box, or TheTVDB page link? The latter would probably also eliminate a lot of alternatives and misspelled show titles if they also point to the same external links. The second being of course, would this be more work or trouble than it's worth?