But what does it all mean!Well this was predictable. With the tech world’s attention focused squarely on the launch of the iPad, it makes sense that two of Apple’s biggest competitors would start furiously waving their hands yelling, “Don’t forget about us!”First there was the curious bit of timing that was Amazon’s front-page promotion of the Kindle. Now Microsoft’s getting into the spotlight-stealing game by sending Engadget a snail-mailed invitation to a mysterious event next Monday.What non-iPad product might Microsoft be launching? Engadget speculates that it could be its long-rumored tablet-alternative, the Courier. But given the cryptic nature of the packaging (a round tube with the words “its time to share”) your best guess is as good as theirs.