I have both my iPod (Touch 4G) with iOS 6 and MacBook with 10.8.latest and I set up iCloud on both, and my contacts and calendar events appear to synch via iCloud but for some reason Notes does not.
I rarely use reminders in the iPod but I have some there, and I just checked on my Mac and all the iPod (iCloud) reminders are in reminders on my Mac, but still no iPod notes on the Mac.
I just re-checked iCloud and it shows Contacts, Calendar & Reminders and Notes checked (along with Find My Mac) but no iPod Notes, and the one note I have on the MacBook does show in my iPod Notes. I just checked it. I changed the content of that one note on the Mac and it changed on the iPod. I changed that note on the iPod and it was really cool to see it change on the Mac, but where are the rest of my iPod notes?
Oh semi-happy joy. I found out what's going on. According to http://support.apple.com/kb/HT4191?viewlocale=en_US, my iPod iOS Settings> Notes storage was "on my iPod", instead of iCloud. Once I switched it to iCloud, a new note showed up on both.
Now I have to figure out how to get the rest of the iPod notes from local to iCloud, as the article (above) says I have to "copy or transfer them to iCloud or IMAP to sync with your other devices", but it gives no directions for that or a link to the directions or what to search for to find that (so only the applicable results show up).