Yes, as Jon says, the nutritional values are pretty much the same (for one of the CD programmes anyway), and there are more choice of flavours for CD.
There are also more choices of plans, so though you can just SS, you can chose to do slightly higher plans that give the same weight loss ie SS+ or 810. SS+ can be done just with shakes (1 extra for some) and has skimmed milk added, which is popular for people who like some in their teas and coffees. Others chose to do a meal with their shakes. The meal is set out and includes certain proteins and vegetables with strict guidelines for quantities.
Some people SS or SS+ but use the meal when they feel they need to eat something (social occassions, so they can sit down and eat with their children or when the going gets too tough and they are just about to fall off the wagon). As I say, weight loss is similar to SS. Others stay with SS.
You can only SS or SS+ for 12 weeks at a time, then you need to do a week of 810. This is to follow the NICE guidelines which state that a VLCD shouldn't be done for more than 12 weeks at a time. LL have a similar rule. I have no idea why LT don't.
After that 810 week, they can chose to go back to SS. It works very well.
CD is sold via counsellors who have done the diet themselves.
Hope that helps