In al the recent previews one certainly stood out for me, and that was the Legion Astartes Whirlwind Missile Tank for The Horus Heresy.
The Whirlwind is a certified Astartes classic combining the venerable Rhino chassis with a huge missile launcher that hurls storms of explosive warheads into enemy ranks, whether it has line of sight or not. The sophisticated range-finding and targeting auspexes mounted to the launcher allow multiple different kinds of munitions to be loaded and fired independently, from standard high explosives to incendiary Pyrax rounds.
The Whirlwind is an Imperial artillery support vehicle based upon the Standard Template Construct (STC) Rhino armoured personnel carrier (APC) chassis that was used by the Space Marine Legions.
This new model reflects the original conversion from 1989. The original Whirlwind was a conversion using a slottabase and plasticard for the rocket launcher. This was published in the September 1989 issues of White Dwarf, #117.
You can see the instructions in this post.
Since 1989 we have seen many different versions of the Whirlwind which have evolved from this original conversion.
I have also preferred the original conversion to the newer versions, so it should be no surprise that I will probably get one of these when they are eventually released.