Neeny - I've read somewhere that crawling doesn't necessarily have to ever be 'proper' and that commando style for some kids is completely normal.

In my family - I never crawled at all. Just used to slide along holding on to the walls or anything I could use to get vertical. One of my brothers started walking at 7 months and was climbing out of his cot at that age too. Nightmare for my mother. Bottom line is there is no normal. Each kid is completely different.