I've only been brewing for a year... so, I still feel very new, too.
But also, very hooked.
Austin Homebrew Supply offers a recipe for an Agave Wit, which I've brewed twice, and loved both times.
In my limited experience with it, agave nectar ferments with a very neutral taste. I would say it thins out the body of the beer in a similar way as honey, but doesn't contribute to a "dry" character like honey does.
The first time I brewed with it, I had hoped for a slight tequila note, as I was envisioning a "Texan-ized" witbier - knowing that tequila is fermented agave - but, no such luck.
My advice is to try agave nectar in spring- or summer-type ales, where a lighter body is a preferred quality. I believe you can substitute 1 lb. of agave nectar for 1 lb. of unhopped (extra-light) extract, or 1.33 lbs. of base malt, as a rule-of-thumb.
Hope this helps. And, I look forward to reading about your results.
I'd rather have a bottle in front of me than a frontal lobotomy. -- Tom Waits