Wifi Broadcom BCM4311 is not working out of box - it is probably wrong recognized. Solution to this is placed here (and it affects many people on both oneiric and precise) http://nfolamp.wordpress.com/2011/10/15/ubuntu-11-10-getting-wireless-bcm4311-working/ . I am reporting this bug from another machine, because I dont have the affected machine (DELL D420) at home right now.
ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: bcmwl-kernel-source 5.100.82.38+bdcom-0ubuntu5
ProcVersionSignature: Ubuntu 3.2.0-22.35-generic 3.2.14
Uname: Linux 3.2.0-22-generic i686
NonfreeKernelModules: wl
ApportVersion: 2.0-0ubuntu4
Architecture: i386
Date: Mon Apr 9 23:03:48 2012
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
SourcePackage: bcmwl
UpgradeStatus: Upgraded to precise on 2012-02-06 (63 days ago)
Status changed to 'Confirmed' because the bug affects multiple users.