(Snippet from Google Documentation)
2. How does Google Web Accelerator work?

Google Web Accelerator uses various strategies to make your web pages load faster, including:

* Sending your page requests through Google machines dedicated to handling Google Web Accelerator traffic.
* Storing copies of frequently looked at pages to make them quickly accessible.
* Downloading only the updates if a web page has changed slightly since you last viewed it.
* Prefetching certain pages onto your computer in advance.
* Managing your Internet connection to reduce delays.
* Compressing data before sending it to your computer.

Later in their documentation they say 'Google will receive your requests for unencrypted pages'. So it looks like it leaves https alone.

I find it funny google has come out with this. I just read an article in Fortune magazine regarding Google competing against Microsoft on their own turf.

Does Microsoft have a web accelerator out yet? If not it wont surprise me if they have one out soon.