I think like everyone else the Russians would have over ran Germany and probably gulped up most of northern/western France, with the allies sallying from Italy and possibly another landing in Normandy, thus taking south France. Then i think the soviets would turn east like they did historically after V.E. and declare war on japan. Quite possibly the allies would then make peace with Japan and open a second front on Russia with the added man power freed up from the pacific.
After that who can say? It would have been a terrible war of
with Germany changing hands many time, huge bombing raids by the allies and probably a blockade too.