Had to register to share the wonderful news
The update for R4i SDHC Dual Core 2013 is NOW AVAILABLE! It can also FIX bricked 2013 cards! YAAAY
Below is the link for the firmware update:
http://pan.baidu.com/share/link?shareid=967244462&uk=1795683192
FYI, the download site is in chinese, just click the icon with the arrow pointing down, download, put the file in your sd card, then run the .nds file on an available DS or DS Lite. Follow the instructions then you're all set.
If your 3DS doesn't want to boot the card, try replacing the "_ds_menu.dat" in the root of your SD card with this one:
http://pan.baidu.com/share/link?shareid=961736620&uk=1795683192
Or you can download the entire kernel here:
http://pan.baidu.com/share/link?shareid=1204718603&uk=1795683192
Mine worked without replacing the kernel files, and this was a BRICKED card. It finally worked after the firmware update
Below is the link to the original R4iSDHC Chinese forum regarding the update (just use google translate for all you non-chinese speaking dudes)
http://www.r4isdhcbbc.com/forum.php?mod=viewthread&tid=18479&extra=page=1&page=1