Aaron Boodman (the creator of Greasemonkey) and others are working on this part of chrome. Aaron had initially tried to get his idea for extensions as greasemonkey scripts into Firefox between 1.5 and 2.0.
Google isn't a small startup. Even if Mac is more important than their extension story, it makes no sense having non-Mac developers working on it. They aren't simply building a GUI, they are doing hard "OS level" work of building the security sandboxes for processes - something that is requiring trail blazing work.
The obvious answer to that is "probably Mac users, and nobody else."
As a non-Mac user (at least lately) -- I'd MUCH rather they work on everything but that, really. And yes, I do realize how selfish that is, but it's probably not that much more selfish than your wants.
If they do, it'll just die because it's not Safari. It makes sense to build the functionality on a platform where people are tolerant of incremental improvements.
Also, they have only provisioned for like 2000 requests a second [1], which seems pitiful for launch day when every one and their mother will hit the site.
