Pros
For starters they invented the home video business and are one of the most highly regarded home entertainment companies in the world. If you are looking for experience at a world class company you can't go wrong working here. These guys created the playbook! You will be exposed to people that are the best in the business (packaged goods at least). Warner has scale and the track record to pitch and acquire almost any type of property and put it through the well oiled marketing and distribution machine. And of course, there's all those free DVDs :)
Cons
My experience at Warner Bros. and WBHE was that career development takes a back seat. The management team is not empowered in this area. Performance reviews don't seem to matter because there is not a proper rewards structure in place. (Unless of course you are VP or above). I would like to see the company be more aggressive in their transition to digital. Sorry, but top management does not have the guts to make tough decisions. Look how long it took them to pull out of HD-DVD! But what happened when they finally did? All the other studios immediately followed their lead and the format was pronounced dead in days. As an industry leader, Warner Bros. needs to step up to the plate more often.