Given how important wireless connectivity is to my projects with Gumsitx, I was wondering if you know a tennative date for the Bluetooth enabled version? 
On a side note, I've been looking into SDIO WLAN adapters for Linux.  No implementation exists yet, but from this post to the linux-wlan group, I have hope:
The short of it says that the poster has gotten a CF version of the Sychip WLAN6060EB chip working with linux-wlan-ng.  He postulates that the SDIO version is just same as the CF version but running across the SD serial interface.
I'm going to post what findings I have in case someone else is looking for linux implementation of the SDIO wireless cards that Socket, SanDisk, and ViewSonic have out now.  These are all based on the Sychip chipset.  I won't be able to really dig into this until May this year, but hopefully someone Google's this posting by then and uses it as a spring board.
Its my assumption that the SDIO version isn't utilizing the SecureDigital "encrpytion" scheme (there's no point, now is there?), so it *should* be possible to write a wrapper to translate the CF calls to SD calls.  For that, I've found many publicly posted PDFs that should help.  Its worth noting that the MMC (multimdedia card) interface is basically the 1-data-wire interface for SDIO.  Most of the MMC docs should be applicable to the SD format as well.  SDIO also supports a 4-data-wire interface that can be significantly faster.
To begin with, there are the Intel Application notes for the PXA250:
http://www.intel.com/design/pca/applicationsprocessors/manuals/278522-001.htm (See section 15 for MMC documentation)
http://www.intel.com/design/pca/applicationsprocessors/applnots/278533-001.htm (Mostly pin descriptions, and a little bit of sample code)
Some more detailed specifications for the SD communication protocal is in section 4 of the following PDF:
http://www.sandisk.com/download/Product%20Manuals/Product%20ManualSDCardv1.7.pdf.  Things really get good around 4.8.4, which gives both the SD commands and their arguments.  Note that this doc is geared towards SD memory cards, not I/O devices, so some of the CMD arguments for I/O are missing.  In general though, the "missing" argument lists should .  There are other, somewhat related docs at http://www.sandisk.com/tech/product_man-main.asp as well.
To help fill them in, we can be thankful the SDcard.org posted some "simplified" documents for us as well at http://www.sdcard.org/join.htm (no, no registration required).  In particular are http://www.sdcard.org/Simple_of_SDIO_Card_Type-A_Spec_v1.0_Draft_C_20020524.pdf (a Bluetooth implementation reference, but a good starting point for SDIO cards) and http://www.sdcard.org/SDIO-SimpleSpec-1.00_A.pdf (which lists ALL SDIO commands, if not their arguments).