Yes, I wish they would, but if they really cared about boosting Android performance, picking up Myriad for their Dalvik Turbo would be a better choice. It's 2-3x faster[1] closing the huge performance gap between Google's JIT and Oracle's.[2]
Looking over the changelog from Android 2.2-4.3, there's no mention of performance tweaks to Dalvik. They even have the father of JIT, Lars Bak, working for them. But he's focused on the V8 JS engine and doesn't provide any assistance with Android.[3]
He's also one of the leads on the Dart VM [1], but that likely just leaves even less time for involvement in anything Java/Android.
[1] http://www.dartlang.org/