For some odd reason, I never hit publish on this. It’s since been overtaken by the release of the 2.2008-50 release which I’m currently trying to get my hands around. Expect an update shortly.
I’ve finally got around to getting the Maemo 4.0 dev environment so I’ve now been able to build a new kernel with the highspeed MMC/SD patch applied. The docs are not super clear but I believe this same kernel image is used for both the N800 and N810 – I’ve only tested it out on my N800 as the N810 isn’t released here until the 19th. Although the N810 only has a miniSD slot, this patch is still useful as it’s possible to get miniSD and microSD cards that can operate at 50MHz. However, N810 users should note that I have no idea how the internal 2GB eMMC reports itself and how it will interact with highspeed operations. It’s a Samsung part that’s basically just the guts of an MMC card soldered to the board but it does have some differences. I’d be interested in hearing any reports and I will obviously check for myself once I get my hands on one.