Some vehicles, especially where it is hot out, have had issues with the KLE module (this is part of the built-in charging circuit on the vehicle). BMW identified a fix for this and is building new modules without that problem, but in the interim, if the vehicle does not have the new one in it (yet), to ensure it is reliable, they modify the charging logic to limit the maximum charging rate based on the battery and outside temperature. Where I live, it has been colder, and I have not noticed a decrease in the charging rate (i.e., it taking longer to recharge the vehicle), but some people have noticed it. There were some other minor tweaks to the software, but I don't remember the details - one aspect related to the reliability of the range to empty, but there could have been others.
Expect another software update sometime in early 2015. It's possible that these new vehicles are getting that update, but it's probably a bit early. Can't tell you, don't know.
It is my understanding that the software for the i3 is customized by VIN, and requires their equipment to be hooked up to the server in Germany. TO make an effective connection, it may be that they have to limit how many vehicles they can connect at once - internet connections aren't infinite, nor are the server responses. IT does take awhile to download all of the new modules of software, then verify no hiccups.