The main reason for taking this trip (besides just having fun at Disney, of course!) is to check out Bay Lake Tower.  It is scheduled to open on Aug 4th so we'll be getting there about 3 months after it opens. 
Hopefully, this is enough time to get all the "kinks" out and the resort will run smoothly.
My thoughts on BLT, prior to experiencing:
1.  The ability to walk to MK is an AWESOME perk.  This is truly the highlight for staying at BLT.  No having to fold up a stroller.  No waiting for a bus or driving to the TTC and then getting on yet another vehicle to get to the MK.
2.  Playing devil's advocate:  Will the walk from door to door (BLT room to MK entrance) become a hassle?  You still have to negotiate the hallways, elevators, cross-over bridge, more hallways, more elevators, the parking lot, the road, pass the bus stops and boats to the entrance...
3.  The room decor is rather UGLY.  Most people who have seen the room in photos believe that Disney dropped the ball on the design/decor of the room.  However, those who have seen this in person, say that the pictures don't do it justice and it is nice.  We'll see.
4.  The prime location at BLT is to get a Magic Kingdom view.  Next is a Lake view.  We are in a standard view which basically means overlooking a parking lot.  Will the standard view be good enough?
When we go to Animal Kingdom Villas, we love having the savanna view to watch all the Watusi, Zebras and Giraffes.  What about watching the Odysseys, Camrys and Cherokees??
5.  Will we regret not having a car?  Is Magical Express all that magical??  
The last 4-5 trips or so, we've gotten a rental car and it was wonderful.  We like to visit the restaurants at the resorts, we like to go to Wal-mart for essentials and groceries and I don't like waiting in line.  I actually do like driving and it's nice to pack some extras like snacks, food, change of clothes, water stuff (ponchos, umbrellas, etc) if we need them.
6.  If you don't get your own MK view at BLT, then you can go to the BLT Lounge to see the fireworks along with the piped in music.  However, since there are more people who won't have MK view then will be allowed in the lounge, I'm wondering how crowded this will be.  Will there be plenty of chairs or will it be SRO?  If SRO, will there be a special place so the kids can see the fireworks?
I wonder if this is just a room or if there will be any amenities there like food or drinks to purchase.
7.  Disney's newest DVCs are changing up the 1BR.  They are now sleeping up to 5 (one bed, one sofa bed and one sleep chair).  They are also putting in a 2nd bathroom in the 1BR.  I'm sure we will come to love the 2nd bathroom.  It will certainly make getting ready easier in the mornings and after swimming in the pool.
8.  Amenities:  BLT is going to have its own pool and slide.  I'm hoping that we'll get a chance to use this...however, weather in November can start to get cool, and even if the pool is heated, it can be a long, cold walk back to your room.  So we'll definitely pack a swimsuit and at least walk around the pool area.
Also BLT has all the water sports and beach area that the Contemporary Resort has, so I definitely see those "water mice" in our future!