Impossible to list only user installed packages

Suggestion:
It would be _extremely useful_ if the above mentioned function had an option to _only list those packages explicitly selected by the user_.
i.e. Not packages automatically selected as a dependency to something the user selected.

This would amount to an "User Installed Applications" list that would be very helpful for setting up other systems (possibly with different OS versions) without the cruft that a comprehensive listing causes.

This would also be useful for failed dist-upgrades (which I've had happen before). I'd like to be able to easily list the packages I've installed so that if I need to reconstruct the system from scratch, I can.

Additionally - it's important to be able to quickly determine how UEC/Ec2 instances are configured. This would be very helpful and very easy. Seems like taking the difference between the output of dpkg -l on a fresh installation and a current installation would accomplish this.

It is impossible for us to determine which packages were installed by you.

It is not impossible, it is quite simple, just get the list of installed packages and subtract from it the list of packages on the default system installation.

Also, apt should have some kind of log, this way you could list all installed packages between some date. Also, we could see all changes filtered by date. Something like:

$ apt-get log 2011-01-01:2011-05-01

And that should return something like:

2011-03-10:
Installed some-pakage-name 0.1.2
Installed other-package-name 1.5.6
Removed another-package 2.3.4
2011-04-05:
Upgraded some-package-name 0.1.3