In next week's White Dwarf there is apparently a free Kight poster that on the reverse has the entire range of Cult Mechanicus listed and shown. Whoa, the leaks are coming, and the model range looks fantastic.
This gives additional support for the codex unit lists we saw just recently. http://natfka.blogspot.com/2015/04/forces-of-cult-mechanicus.html
Here is a couple places you can see these images.
Bolter and Chainsword
Blood of Kittens
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