When Canonical started developing the Ubuntu Software Center, I knew that a time will come when it will completely replace Synaptic. The Software Center is a noob-friendly replacement for Synaptic where users can discover new applications more easily.
The Software Center had already taken over the function of Gdebi in Ubuntu 10.10 Maverick Meerkat and Gdebi is no longer included in the Ubuntu ISO. Unexpectedly, Canonical has decided that it is time for the Software Center to replace Synaptic as well. So, in the next daily build of Ubuntu 11.10, Synaptic will no longer be installed by default.
The decision to remove Synaptic is a very unexpected one. Yes, the Ubuntu Software Center looks prettier and new users are more likely to use it, but it does not have nearly as much feature as Synaptic does. Many of the features that are missing in the Ubuntu Software Center right now are very crucial features. Here is a list of some of the features that Synaptic has but are still absent in the Ubuntu Software Center:
Fix broken packages
Upgrade or downgrade a single or multiple packages
Lock packages to a specific version
Force install of a specific version of a package
There is still four months left till Ubuntu 11.10 gets released. I hope that is enough time for Canonical to add these missing features.
Synaptic will continue to be available in the repository, though, and can be installed with
$ sudo apt-get install synaptic