Microsoft Corp. last week kicked off a $150 million-plus global brand campaign for its newly upgraded MSN Explorer with a :30 titled "Butterfly." McCann-Erickson Worldwide, San Francisco, breathes life into Microsoft's butterfly icon; it flutters across a diverse group of people and settings, as the advertising shows how the Internet portal and online access service can be integrated into everyday life, no matter where you are. The new tag is "MSN, make it your home." Copywriter: Sam Avery. Art directors: Ruth Rosenfeld, Simon Chandler.