It is now possible to send a text message to a BT landline. I've had a couple from a M8.
It sounds a bit strange to start with as it's all automated (a bit like the speaking clock) and it asks you if you want to hear it.
There is no operator on the other end so your right to put the phone down on those!!
The BT privacy thing is not quite what they say it is, sure you get free caller display (which normally costs about £5 a quater) but the only other thing BT do is to sign you up with
The Telephone Preference Service which you can do yourself and you can sign up to the Mail Preference Service and the Fax Preference Service at the same time, which I don't think BT will do for you.
I still wish that there was an "opt in" list you could sign up for to receive mail, fax, phone and email cr@p instead of having to "ops out"!!