Pocket nappies (eg. greenkids) aren't so great for newborns because they only layer one layer of defense against poo!! DS used to leak in these until he was 3-4 months old (he was a big baby - I've heard others say 6 months). Mainly the leaks were wee out the leg - they just didn't fit properly when he was small.

We used BBH bamboo & hemp fitted nappies from when he was about a month old. These were great & we still use them now. Easier than a flat nappy because there is no folding & they are really absorbant. They fitted really well (probably could have used them from day 1, but was just a bit scared to start!). They were a bit bulky to start though - we had to move up to the next size clothes.