Sorry, I know it is not a new thread, but this just happened to me for the first time (including the congratulations message)... However, I was able to delete the item normally when I went directly to the "watch list" instead of the eBay summary (from the My eBay dropdown menu at the top). There is no logical reason why the item could be deleted directly from the watch list page but not from the watch list appearing on the eBay summary page, where I had tried several times to delete it (I guess it is a glitch). Anyway, maybe others can try the same trick if the problem happens to them. Go to the My eBay dropdown menu, select Watch List, delete the item - done!
