Adobe Lightroom 4.1 release candidate 2 is now available for download from Adobe Labs.

This release includes new Defringe controls to help address chromatic aberration, and the ability to read 16-bit, 24-bit, and 32-bit HDR files.

Defringe is available as part of the Lens Correction panel, as shown below.

Defringe Corrections in Lightroom 4.1

What exactly is a color fringe correction? Well, rather me try to explain I’ve linked to any excellent tutorial written by Eric Chan (Lightroom and Camera Raw engineer)

New Camera Support

• Canon EOS 5D Mark III — introduced with release candidate 1 (March 29, 2012)
• Canon EOS 60Da
• Fuji FinePix F770EXR
• Fuji FinePix F775EXR
• Nikon D3200
• Olympus OM-D EM-5
• Panasonic Lumix DMC-GF5
• Pentax K-01
• RICOH LENS A16 24-85mm F3.5-5.5
• Samsung NX20
• Samsung NX210
• Samsung NX1000
• Sony Alpha NEX-VG20
• Sony SLT-A57

More details on bug fixes, etc can be read on the Lightroom Journal