Rated 4 out of 5 stars
Edit 3/29/11: Have registered at addonsmirror.net & activated acct - can't post. Contacted Admin - no reply. Bummer.
Problems in FX 4:
-When view cookies for current site or All Sites, the Remove Cookie and Remove All Cookies buttons are GRAYED out. Only way to del cookies (I found) from CM is select cookies individually in a domain, then hit Del button on kybd. Or can select the domain name (containing all cookies) & hit Del.
-Can't access CM menu / options when on a blank tab (maybe also when a site doesn't req setting cookie? as Trasd said).
-Kudos on having it updated for Firefox 4.0 Was using Cookie Safe & even though Fx allowed it to be used in Fx 4, couldn't get it to work. :( Cookie Monster 1.05 seems to work OK in FX 4, so far (not too much testing). It's a little diff from CS, but not so much that anyone experienced w/ cookie mgrs couldn't figure it out pretty quickly.There are fewer options than w/ CS, but may not be a bad thing. Time will tell. More isn't always better.
-Note to reviewer kda: Maybe you don't want the "addon bar" at bottom of screen (it's very small in FX 4). For those that do & haven't figured out how to enable it for certain addon icons, R click an empty space above the tabs, then click "addon bar." As far as moving such icons to top of screen, don't know yet.