$ apt-cache search picasa
picasa - Picasa is software that helps you instantly find, edit and share all the pictures on your PC.
You can also ask APT to show info about this Picasa package:
$ apt-cache show picasa
Package: picasa
Version: 2.2.2820-5
...
Just how much extra software will Picasa require to be updated? Check for dependencies with the following:
$ apt-cache depends picasa
picasa
Depends: libc6