Microsoft is right now officially launching Windows Server 2008, so for those who like lists, here is a bullet point list of new or improved features we thought worth highlighting. It's officially "Microsoft Windows Server 2008 SP1" to keep it in line with their desktop product Vista, and licensing details are being published very soon.
 

• Faster Install
• Windows PowerShell, a new optional command-line shell
• Better remote server management
• Componentized Server Core installation option allows minimal installations where only the server roles and features needed are installed
• Windows Deployment Services (WDS)
• Better Failover clustering
• Windows Server 2008 Hyper-V allows separate virtual machines (VMs) to run on a single physical machine, even Linux virtual servers
• New storage features, such as pass-through disk access and dynamic storage addition, allow VMs more access to data, and give external programs and services more access to data stored on VMs.
• Terminal Services (TS) RemoteApp and TS Web Access allow programs that are accessed remotely to be opened with just one click and appear as if they are running seamlessly on the end user's local computer.
• Addition of TS per User Client Access Licenses (CALs) tracking (previously only Device CALs tracked)
• IIS Manager, a new task-based management interface, plus a new appcmd.exe command-line tool
• Delegated administration of applications and sites lets you give control to different parts of the Web server to those who need it.
• Integrated Web server health management for improved visibility and tracking of requests running on the Web server.
• Enhanced application pool isolation for greater security and stability.
• Security Configuration Wizard (SCW) helps configure the operating system for the server roles being deployed to reduce the attack surface area
• Network Access Protection to assist in isolating and/or remediating those computers that don't comply with your security policies
• User Account Control provides a new authentication architecture for protection against malicious software.
• Read Only Domain Controller (RODC) allows for local authentication of users in remote office locations using a read-only replica of the primary AD database.
• Active Directory Federation Services (AD FS) enables trust relationships to be more easily established between partners with different identity and access directories running on different networks, enabling secure single sign ons (SSOs) to each other's networks.
• BitLocker Drive Encryption provides enhanced protection against data theft and exposure of server hardware if lost or stolen, and it provides more secure data deletion when your servers are eventually decommissioned.