Based on an initial test drive, Vista RC1 is the first version of the forthcoming Windows operating system to show true refinement, both in terms of reliability and overall performance. For this story, Computerworld worked with Vista Build 5600 on five test machines for a period of about 48 hours. It's the tip of the iceberg, offering initial impressions that will be followed by a more exhaustive review in the days ahead. But during the first two days, Vista RC1 didn't disappoint. For the first time, it feels stable enough to run on a production PC.

Performance takes many guises. Microsoft is promising 2-second resume times from Sleep mode that don't degrade over time. Another performance boost comes from smartly balancing the usage of CPU time. Microsoft is giving background services, like Windows Defender, lower input/output priority to increase the performance of your line-of-business applications. In particular, it aims to make applications load quickly and to maintain that state of alacrity over time. It's too early to say whether the software maker has achieved that in RC1, but resume-from-sleep times are in the 3-to-5-second range. And applications such as Microsoft Word appear to pop open quickly. Time will tell.

Nuevo networking

RC1 introduces a fairly radical overhaul of the Network and Sharing Center. It merges two previous networking control panels into one, and reworking the functionality makes it truly useful for the first time. The new Manage Wireless Networks task area finally gives wireless networking users a logical, useful way to control named and saved Wi-Fi connections. You can right-click the Network desktop icon and choose Properties to open the Network and Sharing Center. Or click the Network icon in the system tray to initiate a new network connection.

Networking controls have never been a Microsoft strong suit, but even so, the Network and Sharing Center, as well as the tasks it offers, form the best networking control interface that Windows has ever had.