The BBFC has published a list of what will be included on the bonus disc that comes with Gears of War 2.
Don't look if you're not keen on spoilers, but you can see for yourself over on the BBFC website.
There you'll find a full list of the items on the disc. Apparently it the linear elements, e.g. cut-scenes, run to 148 minutes and 40 seconds. The BBFC has given the disc an 18-rating, without feeling the need to chop anything out.
Gears of War 2 will be released on 7th November.