This time, since it was vacant and I had assistance, we went around and looked from the back as well:
I'm guessing it took them most of the day yesterday to put all those pieces together and get them braced. I was hoping they would pour them, but I peeked in and they're all empty. Guess the concrete guys don't work on Saturdays! Either that or they knew it was going to pour this evening (which it currently is) and they wanted to wait. I feel better about what they're doing now that I see the wall frames up...they're going to backfill the dirt pile I was standing on to cover up all that basement wall my friends are standing in front of, and then everything will be on one level. I guess that means our basement floor will be more like an upper floor, framing-wise? The back is open because we get a rear-stud wall with our walkout, which essentially just means that our rear basement wall will be studs and plywood just like the rest of the house (maybe that was really obvious, but I didn't realize what that meant at first!).
In any case, I'm going to swing by there tomorrow since it's on my way, but I don't anticipate any changes. Originally I was only going to stop by when it was just me and #2, but it's too exciting! So I'll limit myself to one trip a day. Once they get the roof on there won't be much to see from the road anyways, and I won't have any choice but to stick to my original plan...I'm not taking two kids inside there by myself!