Congratulations on your twins!
I was planning a birth center water birth with my midwives. Then I found out at 28 weeks that I was having twins. We had one other u/s at 20 weeks, but we only saw one baby, for whatever reason. I got REALLY big suddenly, and my mws made me get another u/s at the 28-week appointment, or we might not have known about the second baby. I asked if they would still attend my birth, and they said it depended on the placenta situation (two seperate, or one), positions of the babies, etc. We didn't have alot of time to discuss it further, because 2 1/2 weeks later I went into premature labor while out of town, and ended up giving birth at a hospital four hours away from home.
I don't know to this day if my babies shared a placenta or if it was two that were fused (I never went back for a postpartum appt., and don't know if the OB would have known, anyway). All I know is that the placenta of the first baby remained inside, and was one of the reasons I ended up having a c-section 6 hours after the first baby's birth. They were in separate sacks, though. They were the same size when born, so there wasn't any problem with TTTS.
The u/s tech at 28 weeks told us that the separate sacks meant the twins were fraternal, so I assumed they were. But the girls had a nurse in the NICU who had given birth to identical twin boys in separate sacks, so I don't know now. They look just alike. I need to do one of those tests to find out for sure.
As far as double strollers go, I have a Graco stroller with "stadium" seating, and a Jeep stroller that is side-by-side. I have never used the Jeep one. Both were given to me as gifts. What I *really* wanted was a tandem jogger, because I live out in the country, and the other two are not good on dirt roads. Oh well... I do like the Graco one, but it is big, and I don't get out of the house much, so I don't use it alot.
Good luck to you...you will find out everything (or damn near!) you need to know on this forum