Advanced system packaging tool ‘Synaptic Package Manager’ has been dropped from the latest builds of Ubuntu 11.10 Oneiric Ocelot.
The removal of Synaptic Package Manager is not unexpected, having been planned since the inception of the Ubuntu Software Centre. Many of the advanced features Synaptic currently provides are ear-marked for inclusion in the Ubuntu Software Centre.
Synaptic will remain easily installable from the Ubuntu Software Centre.
Due to the development nature of Ubuntu 11.10 decisions and actions are subject to evaluation and change.
Source | launchpad.net