I've gone from super alpha CM7 to CM7.1 and current nightlies without wiping, save for once, and that was due to Google Apps changing.
CM6 -> CM7 you have to wipe, but most OTA updaters will tell you that the OTAs from Eclair->Froyo or Froyo->Gingerbread effectively require a data wipe anyway. My mother had issue after issue after the Eclair->Froyo OTA and they went away when she did a factory reset (wipes /data).
>Ideally I'd like to see Google offer APIs to apps so that their data is continuously synced to my google account
They exist, though there is some fine print about device compatibility that is a bit wonky and NO one seems to use them for anything. I agree. I think this is the missing feature in a large way. I hate having to remember to turn off the loud beep in QR Scanner when I wipe my Droid (it's speaker is sooo incredibly loud). Things like that would be trivial to store in text config and/or sync with Google.
>CM6 -> CM7 you have to wipe, but most OTA updaters will tell you that the OTAs from Eclair->Froyo or Froyo->Gingerbread effectively require a data wipe anyway. My mother had issue after issue after the Eclair->Froyo OTA and they went away when she did a factory reset (wipes /data).
I just checked and 7.1 doesn't require a wipe, I was under the impression that it did. Is it that only when the upstream major android version changes that you need to wipe? A quick googling leads me to believe at least Google's official OTAs for the Nexus line don't require wiping.
CM6 -> CM7 you have to wipe, but most OTA updaters will tell you that the OTAs from Eclair->Froyo or Froyo->Gingerbread effectively require a data wipe anyway. My mother had issue after issue after the Eclair->Froyo OTA and they went away when she did a factory reset (wipes /data).
>Ideally I'd like to see Google offer APIs to apps so that their data is continuously synced to my google account
They exist, though there is some fine print about device compatibility that is a bit wonky and NO one seems to use them for anything. I agree. I think this is the missing feature in a large way. I hate having to remember to turn off the loud beep in QR Scanner when I wipe my Droid (it's speaker is sooo incredibly loud). Things like that would be trivial to store in text config and/or sync with Google.