Since I anyway needed a second tuner, and it is vacation (with time to spend on computer), I went ahead and bought the Nanostick.
Upgraded my kernel to git 3.0.0 rc6 and used the media build script.
Happy news are; it works somewhat! ;-) In detail;
What works:
SVT2HD shows up in the services list.
Recording of SVT2HD work just as good as any other SD channel. :-)
What does not work:
Not all HD channels can be found. E.g SVT1HD. Not sure why, but I guess it is on some new frequencies or something(?).
The Nanostick seams less stable than my old FireDTV. For some reson; as soon as I open a ongoing recording (SD or HD), the recording stops, dmesg says;
[ 3149.906220] ehci_hcd 0000:00:1d.0: shutdown urb ffff8802143f0000 ep4in-iso
[ 3149.906225] ehci_hcd 0000:00:1d.0: shutdown urb ffff880232801000 ep4in-iso
[ 3149.906228] ehci_hcd 0000:00:1d.0: shutdown urb ffff880232804800 ep4in-iso
[ 3149.906231] ehci_hcd 0000:00:1d.0: shutdown urb ffff88023104a800 ep4in-iso
[ 3149.906233] ehci_hcd 0000:00:1d.0: shutdown urb ffff88023104e800 ep4in-iso
But if I leave the record alone, all seams well. Cannot make out if this is related to the Nanostick drivers or tvheadend.