Comet C/2011 L4 (PANSTARRS) - updated

Information on this comet, which may become visible to the naked eye, can be found here:

Cometography
Wikipedia
Space.com
British Astronomical Association
Minor Planet Center
Spacedex

There are, no doubt, many other sites with information. If you know of any, or have more up to date information, please feel free to add them via the comments section.