In addition to the already mentioned Hilton HHonors Promo for the first quarter of this year, there’s another promotion:
Earn additional 500 bonus miles per stay with Miles&More between January 01 and March 31.
You need to register for this promo as well.
Edit: Rumors are, that this promo cannot be combined with the 1000 bonus points promo. No confirmation yet.
Regards,
Dieter