He's going to eat a lot of greenstuff to fill all those holes! But he should end up a huge fat very Nurgley Knight.
Pictured alongside an Imperal Knight and one of my other Dark Mechanicus Daemon-Knights for scale / size comparison.
I probably won't do much more on this guy until the New Year, I'll be back on my Vikings & Saxons once I've had a chance to spray them at the weekend.
Larger pics up at my Flickr gallery.