I am in love with slings. All slings. I had a backpack carrier when my daughter (now 6) was tiny, and I used it all of twice. It was uncomfortable, awkward, and just generally unpleasant. So I made a pouch sling when she was about 4 months, then a ring sling when she was 6 months. My ring slings got used with her, off and on, until she was FOUR! The last time she was in it was three months before her fifth birthday, when I was 5 months pregnant!!! She was sick, and I had to take her to class with me. Seriously, though, it was that comfortable.
And I love how adjustable they are. I can nurse a baby, prop them up to burp them, then move them onto my back so I have easier access to look at things in a store, all without having to actually take the baby out of the sling. And without exposing myself, which is a real feat, since I'm, er, busty, and my son has always been a restless nurser. Even now, my 14 month old will crash almost as soon as I get him in the sling.
I tried a wrap sling this time around, and I really liked it. It was really convenient and comfortable once it WAS on, though. It was a bit tricky to learn to do, so I recommend getting a pouch or wrap first, just to get used to slinging.
To sum up, LOL
pouches fit nicely in diaper bags and have "throw 'em on" convenience.
rings are the most versatile. They can also be used as changing pads, blankets, and the tails make great burp clothes and snot rags (I have several so I can just wash them often)
wraps come in such pretty fabrics, are a bit tricky to learn, and are SO GREAT when you get them figured out.
http://www.mamatoto.org/
That link has everything you ever wanted to know about baby wearing and then some. Enjoy the new baby!!