I'm having the same problem at my work place with Firefox 3.6.7. It takes about 1 or 2 minutes for the My Pogoplug page to load. Oddly enough this isn't an issue with Internet Explorer. In IE it loads instantly. I can't figure out what's the difference.

Apparently it's a beta build.
http://www.mozilla.com/en-US/firefox/3.6.7/releasenotes/

I've tried IE 7,8 and Safari. All work fine. Like I said, I'm not sure what Firefox's issue is. It's like the page takes a long time to load, but even before it goes and tries to connect to my device. I thought it might be an add-on, but I had the same issue in safe-mode (which disables all add-ons).

BTW Firefox 3.6.7 will eventually become a release version. It's in release candidate testing. You can get it at http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/3.6.7-candidates/build1/

Well that didn't take long. I figured out what's causing the issue. The problem is that I have the "network.http.pipelining" preference set to true. This setting enables sending multiple HTTP requests without waiting for a response (pipelining). This speeds up Internet sites and works well with pretty much every web site out there, but it's causing issue with the My PogoPlug login site. If I turn that setting off the site loads instantly.

See:

http://kb.mozillazine.org/Network.http.pipelining for more details on this.

Thanks.