App won't update in Market

[silverfang77]

I have the latest version of the Market and it says there's an update available for the Complain App (allows you to complain about companies via Twitter and get your complaints heard). The update is listed under Manual Updates. When I touch it and go into the app's update page, instead of an update button, there's an open button. How am I supposed to update this app?!

Thanks.

edit: Never mind. The update button showed the third time I tried.