This has been in the works for sometime, but MSFT formally announced its earnings yesterday, and broke out the MSN unit’s numbers for the first time. Headline: It’s all about paid search. The highlights (from the MSFT IR site): MSN had 50% quarter-to-quarter advertising revenue growth, total revenue totaled $491 million in the first quarter compared to $427 million in the prior year’s first quarter. MSN Subscription revenue declined $17 million or 6% reflecting a decrease in the number of subscribers. MSN Network services revenue grew $81 million or 51% as a result of growth in paid search and strong general advertising sales across all geographic regions.