Here's everything I know about 1.04:
Ju-88 A4:
Possibly other variants; Superfly said he had a few different types flying around in his head. No doubt the demons, other 7 personalities, and his conscience are tired of getting bombed
Lancaster:
4k max. bomb size according to Pyro. Natedog probably has started speaking with a British accent by now
Ostwind:
Self-propelled 37mm AAA gun based on the Panzer VI chassis. Great for field defense.
Terrain modifications:
Existing terrain will be fixed in a few areas. Namely, A1 will be lowered, textures will be fixed [square snow patches no more] and other things.
BETA terrain reintroduced with V-fields. Should be LOADS of fun driving up those canyons!
I know there's more, but only if Pyro would tell us
Flakbait