staff:

New iPhone Dashboard interface! Much more functional and much prettier.

If you haven’t yet, you can download Tumblr for the iPhone for free. Enjoy!

Since it’s just a Webkit view, Tumblr doesn’t need to go through the App Store to make updates like this.  I am concerned that using a “Show More” link instead of the old pagination is liable to eat up all the iPhone’s RAM when looking further back, though.