How cute that she doesn't realise she can get out! Although I think thats related to all the hard work you've put in to sleep training so she realises bed is for sleeping, not messing!
We've been toying with potty training for a while now, just practicing using it etc and she actually did a poo in it last week (was doing bare bum time and told me she was doing a poo and I managed to get her sitting in time). She's had a lot of the readiness signs for a while but I've been putting it off. Santa is bringing big girl pants (In the night garden ones which she'll love) so I might just go for it in January and see how we go. It seems like such a big step toward independence though, I think thats what puts me off!