I've taken it before. I just took it again, for fun. Like you, Moose, I based my answers on mostly my worst times that were long-lasting, and an average over my life. My manic episodes have been far worse than my depressions and far more numerous, long-lasting, and dangerous. So, my mania score is noticeably higher.

I had to answer "Quite a lot/All of the time" for most all manic questions. In the depression section, I had to answer more "Somewhats", with a few "Just a littles" and "Quite a lots". I have had a couple disabling pure depressions, but I haven't suffered from pure depression as severely as many (or even most) here. I have had many periods of severe mixed states, but they usually leaned in the manic direction (with a few exceptions). My manic with mixed features episodes were the most dangerous for me. When I'm purely depressed, it's more like I'm just in a near coma and can barely even think (in bed all day) or have so little energy that I feel paralyzed. My score came up as:

Mania Score: 45
Depression Score: 20
Possible Diagnosis: Bipolar I (and Bipolar I is definitely what I have)

The test didn't make any references to anxiety, but though anxiety is not always an issue for me, it has been at times. Sometimes severely. Anxiety can be present in all of my bipolar mood states, except maybe euphoric mania. Anxiety is not much of an issue for me when stable, especially since mastering some coping tools/skills. Cognitive Behavioral Therapy (CBT) rocks!