It was rumored to be happening after signage for Lion was delivered to Apple's retailed stores, and now we've got confirmation. During Apple's earning call this morning, the company's CFO, Peter Oppenheimer, confirmed that Mac OS 10.7 or "Lion" will be landing in the Mac App Store tomorrow.
According to Engadget, the new OS will be available for $30USD and will be a 4GB download, and the server edition (Named "Lion Server") will also be available tomorrow for $50. The new OS from Apple brings many new features to the table and also brings a bit of iOS flare to it as well. Many believe that this will be the start of the convergence of the OS X experience into that of the iOS world.
Initially, stores will not offer a physical version of Lion and instead will sell App Store cards so users can purchase the OS from the App Store. Rumor also suggests that the much anticipated refresh of the MacBook Air line will be made available tomorrow, and additional rumors suggest the Mac Mini and LED Cinema Display may see new models too.