Get out your Salt Shakers folks - and then go get those of your neighbours because your gonna need ALOT of salt with this one.
I might regret posting this if it turns out to be a complete hoax, which is almost certainly is however I'm gonna bite and post it and let people decide for themselves. The picture in the below image was posted on Warseer by a new poster named HaveBlue09, in a newly created Photobucket account HERE in the The Dudes IG Rumour Roundup IV thread, the implication being that this may be a prototype or similar or indeed actually the model for a new Leman Russ kit.
Many people, myself included are taking it for a conversion based on a Baneblade chasis, which it obviously takes many components from. Assuming it is a conversion it's a damn good one and whoever did it deserves alot of praise, but there is the issue of if it is'nt.
I'll admit I'm not as 100% sure as I was that it is a conversion, as having looked a bit more closely at it I picked out on some of the points below in my comparison image. That said I still think it is very unlikely, not least because it's such a complete redesign on a Russ, while leaked pictures from the codex have pointed to no change in this tanks classic design.