Perhaps main reason for this MS is promoting the language at the expense of Visual Basic. Personally, I think it is a shame that a language targeted mainly to a single OS gain such popularity (not counting Mono.)
I find it interesting that the poster mentioned the growth of C# (going from 4th to the 3rd), but didn't mention Objective-C's much larger growth spike (from 8th to 5th place).
To me, that's the bigger story - I imagine all that Objective-C growth is getting targeted squarely at the mobile platforms. That's a lot of dev interest.
I do hope you hold the same cynicism for Objective-C. :P