A few interesting blogs on Mozilla recently:
Jon Udell's weblog
FS Consulting's Weblog
StandBlog (google translation)
Edward Bilodeau's weblog
Words of Waldman v2.0
Evil Fenius Chronicles
(and there were a dozen or so additional blogs that I bumpted into that linked or excerpted Joel but didn't add commentary.)
There are also a a half-dozen or so blog posts I've run across in the last couple of days discussing people trying out (and liking) Firebird. Maybe more ripple from Joel?
Firebird even gets a mention at Dog News: weird, inspiring dog tales :-)
update: If you're looking for more on Mozilla Firebird then don't miss don't miss David Tenser's amazing Firebird Help site, Ben Goodger's great Reasons to switch to the Mozilla Firebird browser doc and Minh Truong's 10 incredible Mozilla Firebird features (and how to use them) page.