I am very happy to see that the new XO-1.5 laptop design will hopefully bring the price per unit down. We'll see if it can really break the $100 barrier. Yet if the plastic case molds are to be redesigned I wonder if it could also be the chance to fix some of the most annoying issues we are all experiencing.
SD Card Slot
The SD reader should be placed anywhere but where it's now. I understand that it was a late addition and it couldn't go anywhere else because the plastic mould would then have had to be redesigned (a costly operation), but please take advantage of the current evolution to put it say near the USB ports on in the bottom case, below the trackpad. Developers will bless such a change!
Since the WiFI chip is going to be replaced with an 88W8686, hopefully it could come with a free WiFi firmware this time, or at least a thin firmware could be available as an option for when 802.1s is neither possible nor desirable. Having the possibly to run one XO laptop in AP mode, and the others in client mode would, IMHO, be simpler and better because it just works fine. No need for fancy untested and non-free firmware.
The internal serial ports (J1 and CN24) pins should be exposed in the battery compartment. From what I've read, the WiFi chip will be field replaceable without having to discard the whole motherboard - this is a good idea. Apply the same logic to the serial port! It is simply a huge waste of time to have to remove everything to plug a cable to unbrick an XO laptop with RTC problems, or perform hardware diagnosis. I'm not sure how much it would cost, but even a hole in the plastic to solder wire leads would be better than the current setup.
If it is possible, the VGA pins should also be exposed in a similar way, so that an OLPC with a damaged screen could be turned into a fixed computer with only some soldering. No need for edid or other fancy stuff - just add the resistors and some holes to solder a VGA port or even just wires. People who will convert an OLPC to a fixed computer will know what they are doing. We all have plenty of screens around - good old VGA CRT which will not cost anything, compared to the costs of changing the display.
The current speakers produce horrible sound. Would NXT speakers of the same size be too expansive to add? I tested that, it works just great - a bit low on the bass, but we aren't talking about a mp3 playback system. Just something decent enough.
Could the membrane keys be closer to each-other ? Learning to type is important - the current keyboard is far too different from other keyboards. Do not believe children have never been exposed to a traditional keyboard - if only at a cybercafe to read/send email. I also think the keyboard should be more like a standard keyboard (ctrl->cap). I'm saying that while I personally enjoy very much the ctrl key where it is ! But that's because I'm a hacker. We shouldn't force our choices to children who first need to learn how to type. This redesign may not be desirable however, because it would introduce a serious difference in the OLPC user interfaces - yet I think it should be mentioned.