If you're looking for an easy way to manage your PicasaWeb images, try Picapy, an application to mass upload, delete or get the URL of your PicasaWeb pictures - nothing fancy, but it's lightweight and very easy to use.
Usage: there are 3 buttons on the right - clicking the "+" button while being outsite of the album will create a new album. Selecting an album and clicking the "+" button will allow you to upload images to that album.
Right click an image in Picapy and then select "Help" to get some info on that image such as it's direct URL or thumbnail URL.
Install Picapy in Ubuntu
Ubuntu 10.10 Maverick Meerkat users can add the Picapy PPA and install it from there:
sudo add-apt-repository ppa:lorenzo-carbonell/atareao sudo apt-get update sudo apt-get install picapy
For other Ubuntu versions (tested with Ubuntu 10.04, I'm not sure if it works in older versions too), you can download Picapy .deb (for both 32bit and 64bit).
Thanks to Lorenzo Carbonell @ atareao.es for Picapy and for updating it with an English translation!