Pats game is on, so can't do anything new at the moment, but I have a few previous responses on his legacy here, as well, I would note, Rommel's legacy.

Part of this legacy is, I suspect, a sort of explanatory myth for the Wehrmacht's defeat at the Red Army's hands. "We were great, so they had to be really great to beat us!" Furthermore, there is an element of the usual soldier's mythmaking & boogeyman construction at work in the general NATO estimation of these generals' capabilities. As discussed at length in modern revisionist historiography (the good kind of revisionist in this case) like Smelser & Davies' Myth of the Eastern Front and this recent master's thesis, there was a strong urge in the post-WWII US Army to learn from Wehrmacht experiences and thereby adopt their hard-earned lessons in fighting the Soviets; in addition to soaking up some rather questionable perspectives on the Nazi-Soviet War and the nature of both Soviet tactics and the Soviet fighting man, the American officers responsible for interviewing Nazi POWs also recorded personal professional assessments of these Wehrmacht officers' counterparts in the Red Army. These assessments, despite being colored by racism, were sometimes quite positive, particularly towards Zhukov who appears to get far more of the credit than he necessarily deserves from the Wehrmacht. These interviews also included frequent reports of Wehrmacht formations outmaneuvered and fragmented by Red Army strikes. Robert Citino discusses the latter in The Wehrmacht Retreats I believe; German commanders complained (both during the war and later to their Allied interrogators) that they would defeat the Russians tactically despite being outnumbered and outgunned, and yet were swallowed up in massive operational maneuvers.

This brings us to the other reason why military history has come to look favorably on many of the Russian generals, particularly the famous ones - Zhukov, Rokossovsky, Konev, Pliyev, Popov, and others - operational art. Operational art is, at the simplest level, the link between tactics and strategy. Soviet theorist A.A. Svechin, who pioneered the concept, summarized it thus: "Tactics makes the steps from which operational leaps are assembled. Strategy points out the path." Previous military thinkers as far back as the late 18th century understood that this middle level existed at some level or another; Jomini called it "grand tactics" and emphasized the importance of organizing battles together to achieve the destruction of the enemy in the early 1800s, for instance. However, the Soviets do genuinely seem to be the first to fully understand it as a phenomenon of modern industrial warfare, and embodied it in their doctrine as the theory of deep operations. Although there were serious hiccups in their implementation of the deep operations theory (especially relating to the massive expansion of the Red Army in the mid-1930s and the 1937-38 purges) they did ultimately achieve great success with it, culminating in the masterpiece Operation Bagration offensive in 1944. Western scholarship began to pay very close attention to Soviet military theory starting in the mid-1970s and reaching a crescendo in the mid-80s, coinciding with both the post-Vietnam reforms in the US and the increasing NATO-Warsaw Pact hostilities of the 80s. The collapse of the Soviet Union and the subsequent opening of archives continued this trend and led to a real renaissance in English-language scholarship on the Nazi-Soviet War; scholars like David Glantz, Antony Beevor, Chris Bellamy and Roger Reese made real landmark contributions to the Western understanding of the conflict and the Red Army's performance, and a big part of this was an improved understanding of the strengths and weaknesses of the Red Army's commanders. This has given Western scholarship a better appreciation for why a good commander was good, and as such has somewhat added to their reputation as good generals (though of course it has also added to criticisms - David Glantz wrote an entire book called Zhukov's Greatest Defeat for instance.)

I hope this answer has helped! My sources are embedded in the post for the most part, but I can supply some further reading upon request.