The greater majority of you really weren't that fond of FM transmitters, the two largest reasons being signal unreliability and overall audio quality. Many of the FM transmitter haters recommended going with solutions like cassette adapters, FM modulators or a full-on dedicated stereo with iPod-friendly inputs.
Among the still-healthy pro-FM transmitter crowd however, there were three clear favorites: Kensington, Griffin and Monster. This was really helpful in narrowing down my options, and I think I'm going to do some more digging on those and what all this FM stuff is about before dropping another ~ $70-80 or more on something like this.
Ultimately, since my wife always beats me to the Matrix anyway (and she already made me sleep on the couch for dropping $80 on an iPod accessory), I opted to go with a $15 cassette adapter for now (on a side note: it's hilarious what accessory makers can get away with by slapping iPod branding on cassette tape adapters these days). I know, I know: a cheap and simple solution for all the awesome feedback you readers offered, but until AOL (remember: they bought Weblogs, Inc. last year. You're reading an AOL blog! Mwahaha!) sends the 6-figure job offer my way, I'll have to wait on the pimped out touch-screen iPod + Car Borg™ adapter (heck AOL, I'll even take a 5-figure job!). When I do get around to finding that perfect iPod/Borg/accessory thingy, trust me: you'll be the first to know. Resistance, after all, is futile.