A couple weeks ago I read The Polish Officer by Alan Furst, a spy thriller of sorts (though a dark and at times meandering one) about an officer in the Polish-in-exile intelligence service from 1939 to 1943. It's a good novel, with a lot of historical detail which is (so far as I know) quite accurate.
Among other things, it provides a brief but masterful description of the chaos and idiocy that was the Soviet response to the warnings of and actual first days of the German invasion of the USSR. (The main character is eventually sent as a liaison between Polish and Russian partisan groups.) As it describes the gradually stiffening resistance (rather than the implosion that the main character watched during the occupation of France), the author comments (in reference to the German believe that once the door was kicked in the entire Soviet edifice would crumble): "They had attacked the USSR, but now they found themselves fighting Russia."
This reminded me of my rather ambiguous thoughts when reading Antony Beevor's masterful history Stalingrad a year or two ago. By the end of the book, I found myself wishing that the German army would somehow survive. Loathsome though they were, there was little to choose between them and the Soviets, and one started to feel it was unfair that (with the Soviets doing everything possible wrong leading up to and in the first weeks of the invasion) the USSR not be defeated.
But life is notoriously unfair, especially on the steppes of Russia. And given that the several million Nazi soldiers who vanished into Russia made it much more possible for the Allies to defeat the Axis, I suppose one should consider it some sort of limited good.
Still, it seems an interesting question of alternate history what would have happened if the Soviet government had sufficiently collapsed under the German attack to leave something of a power vacuum to the East. Would an Allied victory have been possible without Papa Joe over on the Eastern Front? Trying to keep some sort of control over the vast stretches of Russia wouldn't have tied up as many Nazi soldiers as the Soviet army eventually chewed up, but it would certainly have been a massive drain on resources. Though the oil fields of the East would have done a great deal to ease the supply problems that crippled Germany by the end.