Vmware Workstation seems to be the playground for VMware R&D to some extent and sometimes VMware functionality is first shown in Vmware Workstation to only later make into the other Vmware products. VMware Workstation 6.5 packs some of the following cool new features which puts it (again) miles ahead to the other "personal virtualization products" that I really like:

• Unity mode — Integrate your favorite guest applications with your host. Open the application window, enter Unity mode, and the Workstation window is automatically minimized. The guest application windows look just like host application windows, but with color-coded borders. You can access the virtual machine's Start menu (for Windows virtual machines) or Applications menu (for Linux virtual machines) by placing the mouse pointer over the host's Start or Applications menu, or by using a key combination.
  
• Accelerated 3-D graphics on Windows XP guests — Workstation 6.5 virtual machines now work with applications that use DirectX 9 accelerated graphics with shaders up through Shader Model 2.0 on Windows XP guests. Hosts can be running Windows 2000, Windows XP, Windows Vista, or Linux.
  
• More powerful record/replay of VM execution activity — Easily enable this powerful debugging tool, which records full system behavior, including all CPU and device activity. You can now insert markers while creating or playing back a recording and quickly navigate to these markers during replay. You can also browse a recording to replay from any spot.
  
• Virtual machine streaming — You can now download a virtual machine from a Web server and power it on without waiting for the download to complete. Use the command-line startup command (vmware for Workstation or vmplayer for VMware Player) with the URL of the virtual machine. The download can also be paused and restarted. Note that this feature is not available for ACE instances.

• Easy Install option for Windows and Linux guest operating systems — When you create a virtual machine, you now have the option of entering a few pieces of information so that installation of the guest operating system and VMware Tools is performed in an unattended fashion. Easy install is supported on newer Windows operating systems and some version of the following Linux operating systems: Red Hat, Mandriva, and Ubuntu.
  
• Integration with VMware Converter 3.0.3 — This release includes the Conversion wizard component from VMware Converter 3.0.3. You can now use File > Import to create virtual machines from Acronis True Image files in addition to the Microsoft Virtual PC, Symantec Backup Exec System Recovery, and StorageCraft ShadowProtect file types previously supported. You can also convert Open Virtual Machine Format (OVF) appliances. For Microsoft Virtual PC and Microsoft Virtual Server virtual machines, you now have the option of sharing the source virtual hard disk (.vhd) files. 

• New features for VMware Player — VMware Player now includes the following features, which were previously available only in Workstation:
  • While in full screen mode, you can now switch from one powered-on virtual machine to another.
  • Unity mode is available, so that you can open your favorite guest applications in windows on your host desktop.
  • Both Windows and Linux hosts now support suspending the virtual machine when exiting.

• New virtual hardware version — This new hardware version lets you use the following new features if the guest operating system supports them: Add or remove some virtual devices while the virtual machine is powered on ("hot-plug"). Use LSI Logic SAS (serial attached SCSI) adapters in the virtual machine. Hot-add virtual CPUs and memory to guests that support this functionality. For virtual machines with this hardware version, 3-D graphics capabilities are enabled by default for Windows 2000 and later guest operating systems and most Linux guests.

• Replicate the physical network connection state for mobile users — If you use virtual machines on a laptop or other mobile device, enable this new link state propagation feature if you use bridged network connections (not NAT). As you move from one wired or wireless network to another, the IP address is automatically renewed.
  
• Text copy and paste enhancements — On Windows guests, you can copy and paste text in rich text format, and copy up to 4MB of text. (On Linux guests, the old limitations still apply. You can copy and paste up to 64K of plain text.)
  
•  (Experimental) Replay debugging — Record the execution of an application you want to debug and then use the Integrated Virtual Debugger for Visual Studio to examine the recording repeatedly. No debugging is performed during the recording process, so debugging activities do not affect the normal execution of an application. This powerful tool enables you to fix bugs that cannot be reliably reproduced.