Vista hasn’t escaped the need for security updates in the month of June. All together, five updates affect Windows Vista; three critical, and two moderate. All updates affect both 32 and 64-bit systems, and it doesn’t matter if you have SP1 installed or not.
The three critical updates affect Bluetooth, Internet Explorer and DirectX, and are all “Remote Code Execution” vulnerabilities. One moderate update is a potential denial of services vulnerability using PGM (Pragmatic General Multicast protocol). The other is a “Kill Bit”, presumably to disable either a Microsoft or a third-party feature that has security implications.
Two other updates, one for WINS, the other for Active Directory, are required for other versions of Windows, but not for Windows Vista.