I think nobody knows exactly at the moment.
I made my Update OTA, at the point where I've been asked about this subscribtion I carefully read the terms of privacy, after that there's only a "continue" button, no apply or deny, and the update continues. After updating successfully I got the SMS....

What's really annoying, is that - beside of the eventually costs - it seems that there is no way to NOT receive that message (beside it would be blocked by operator, but this does not mean it is not sent to you). After the first use of the handset after upgrading there wil be an SMS sent to Nokia automatically (!) which contains your phonenumber, serialnumber and identificationnumber
This means that Nokia in any case knows your number(s) and is able to use (abuse) it.

BTW - if you read the terms of policy again you'll find that passus, that the SMS' costs come up to standard.

CU - M_99