spam from forum when not subscribed

[hameau]

anyone know why I'd get spam that says "new thread in announcements" ...

Because any logged-in member can send you an email? (Your posts have the 'Email' button below them.)

In your User CP, 'Your profile' -> 'Edit Options', tick the box 'Hide your email from other members.' (and make any other changes to your contact profile). Click the 'Update Options' button, at the bottom.

AFAIK, any new (spammer) member has full rights to send email, PMs, whatever, immediately.