I believe the debate regarding which language is faster is moot for another reason:

The run time almost never outperforms the development time (and other benefits) when one considers which language/tool to use. For example:

• Qt and GTK are insanely slow when compared with other widget toolkits but they are used because they are more complete and ease the development.
• Using the "faster language" theory, everyone should write web apps using C and CGIs instead of PHP (and even java).
• Most programs/products follow the "release early" and perhaps the "release often" idea instead of the "release a perfect product that is very very fast".
• There is no reason to choose language X if it is faster when there are no developers using it out there. Who will code the program?

Thus, I highly doubt that the speed of a language will ever affect the initial product/OS adoption. Instead, the support and the abilities will do. That's why I was talking about the 'initial' release.

Also, as a personal opinion, speed is not everything. Better provide more that provide less and make them faster. You can only compare two existing products for speed. Not one that exists and it is slow and one that doesn't exist and it would be faster if it was ever written. Android already has a ton of apps and mobile phone manufacturers can instantly take advantage of them. No manufacturer (or human) currently cares if the apps in android's app store are slow.