My DS is 3.7 and I still give him a cuddle and milk in a bottle before bed, and he still wears a nappy at night (he's dry in the morning about 3/4 nights out of 7 so its not something I want to risk just yet!) He also has a dummy at night but absolutely not during the day (basically he seems to revert once he is tired / in the night.)
We have also, and I agree this is a bigger deal, ended up co-sleeping - this is just how its ended up due to various reasons (he kept moving sideways in the night so waking constantly in the cot, DH is in the spare room due to snoring and, besides, we have only just converted the loft where DS would be sleeping if we weren't also meant to be moving house, a plan in itself which has dragged on for nearly 18 months - so basically he was meant to be in his own room next to ours since 2 but we have had a nightmare with house sales falling through and chains collapsing so it's been put on the back burner.)
We now are talking, with enthusiasm from both sides, about when he has his own room in the 'big house' (which will also be next to ours rather than upstairs) which he is very excited about so I am planning on tackling that properly when the time comes rather than putting him upstairs next to DH's office, and having DH and his snorey ways back in with us with no option of a spare room!
In every other way he's a very confident and happy little boy but I do feel a bit conscious that most of his peers, admittedly most who now also have younger siblings, are fully out of the bottle, milk, dummy etc stage.