thedetective I will have 2 years 9 months between DD and new baby. DS will be nearly 6. Glad I'm not the only one whose nausea has got worse since 10 weeks (I'm 10+5 today). I was hardly nauseous at all last time and I'm finding it pretty hard going with looking after the other kids too!
I have a BJCM GT too. I will be using a sling mostly, but am looking at some kind of liner/headhugger/cocoon thing maybe for the main seat so I could in theory use it for baby. DD is rubbish at walking just now, but she has a while to get used to the idea, and to be fair our lifestyle means we're not actually walking long distances.
Anyone who is not used to slings, the best advice I could give you is to get to a sling meeting when your baby is born. A lot will depend on your babies temperament too. My son was happy to sleep in a pram or cot, my daughter was seriously unsettled and colicky and just wanted to be held constantly, so a sling wasn't just useful, it was essential!