The last few days we have been talking a little about mini-dex's and of course yesterday's rumors discussing Mechanicus Adeptus (which is an amazingly popular subject GW nudge nudge). So later in the day yesterday I received an email from a very good source helping us out so that we do not stray too far off course from wishlisting and speculation.
Here is what he said on both subjects...
Please remember that these are rumors, but from a very good source here to help.
via an Anonymous Source
GW is not introducing any new full armies. They're really happy with the spectrum of options currently available.
Forgeworld is adding a few mechanicus units per Horus Heresy Book, that by the time they're on the 3rd or 4th book will have enough options for a full list.
There are still ideas about mini-dex's that have very few options and are very one dimensioned.
1 HQ choice
1 Elite/Fast Attack/Heavy Support
Granted you could run it as a pure army but it wouldn't work very well.
They're a ways out. After all the codexes are updated.