Hi Tomasz,
As explained at
https://developers.google.com/compute/docs/gcutil/, a transition is currently underway to move from standalone utilities like gcutil and gsutil to a unified Google Cloud SDK. This got initiated before anyone had built a gsutil deb; we're thinking that packaging gsutil should now be done as part of packaging Cloud SDK. We'll reach out to Debian about that effort, but we're first fixing some related issues to make that easier.
On newly built images, there should be no need to upgrade gcutil; via the pigeon repository we provide a deb of gcutil 1.13.0, which again is temporary until proper Cloud SDK packaging occurs. We will probably update the official Debian images soon since Debian 7.4 will be released this weekend.
A related note is that, although the Cloud SDK includes gsutil as well as gcutil, the gsutil web page currently still describes the tar-based installation method.
Therefore, for now it's simplest to port the current logic for both gcutil and gsutil. We appreciate your help on this transition!
- Jimmy