I just got a Note 2 cpl days ago and most of my regular contacts have iphones. I can send them a text but when they reply, their message was going to some other iphone user. I have to ask each of them to follow this procedure and so far its meeting with success though I have no idea why:
a) they need to delete my previous contact record
b) they need to create a new contact record with my new number
c) they need to temporarily turn off iMessage on their phones.
d) they then send me SMS or MMS and I have to confirm it it works ( I receive it)
e) then they turn iMessage back ON, wait 5-10 minutes and SMS/MMS me again
This has worked for 3 diff family members. Interestingly, we do have to wait 5-10 minutes in step E. If they try to send me the msg right after turning iMessage back on, I won't receive it.
I know a lot of you guys probably have dozens of contacts and don't want to do this but I don't have so many and its been working.
This is just another in a long line of system incompatibilities that are leveraged as sales & marketing tools by the big software vendors. OS', Browsers, email systems, productivity apps, the list goes on and on... at least we're lucky to have some workarounds..
Good luck -