I tried that out but I couldn't find the menu item "Script"

I've a domain with Apps Script enabled (I'm not a coder, it doesn't help me that much). Long-time Blogoscopers who would like to try scripts can email me.

Brandon, did you receive a confirmation email? You will be invited to log-in via docs.google.com/a/tryscript.com

"You will be invited to log-in via docs.google.com/a/tryscript.com"
People Jonathan Rochelle invited will get a TRYSCRIPT.COM sub-account with an e-mail address @TRYSCRIPT.COM They will need that e-mail address to log in at docs.google.com/a/tryscript.com

Note even though JR has stopped inviting for now, you should still apply for a TRYSCRIPT.COM account if you are interested in testing out Google Apps Script.
By doing so you let the developers know how much interest there is in this new feature and JR undoubtedly will make some effort to be able to invite you after all. The more testers, the merrier!