Pros
Many of the engineers are very good and a pleasure to work with, but it's not as great as it once was because of sheer scale. When you have perhaps 50 of the top 100 engineers in the Valley that's a much stronger statement than when you have perhaps 1000 of the top 2000 engineers in the Valley.
Kontras
The company's core excellence is in the ESX teams, the smaller but well-established development groups like the VI Client, and the long-term employees in other well-established teams. Unfortunately the core ESX product has been commoditized and the company needs to survive on the efforts of teams which have been scaled up rapidly with less attention to quality and especially less attention to management. The crucial VC Server team is particularly poorly managed. Middle management and product management has become shell-shocked or worse, losing sight of overall product quality and usability and fanatically emphasizing exciting new technologies that give bragging rights even when those technologies are not quite ready for delivery and will be used by only a fraction of customers; meanwhile the features that would really improve user experience are sidelined and existing usability features are gutted willy-nilly when they conflict with the latest poster child.