The jogging stroller saved my sanity when DD was little! When she was little and didn't nap well, I'd toss her in there and we'd go for miles and miles... she'd conk out 20 minutes in, and I just kept going until she woke up.
Invest in a good one -- it'll be your best friend! -- and get the car seat attachment. I think that the general guideline is that they have to be 8 months or so to ride in it unsupported (I waited longer with DD, because she was tiny) so the car seat attachment is well worth it.
Keep in mind that the stroller + car seat + baby really adds up. I swear it counts for both cardio and resistance training! ;) Don't get discouraged when your pace plummets... when you get out to run without the baby, you'll FLY.
I have a BOB stroller and I'm still using it 3 years later (though now I have to bribe DD with new iphone games to get her in there). I've trained her to say "YAY, Mommy!" and "Go, Mommy, go!" at intervals... it's very motivating.
| current weight: 129.4