Amy (my name too!

)
It's tough one, because right now, if you want GOOD iPod support (not just an FM Modulator) there's nothing available compatible with the Navigation/Bose system. So, if you buy the car with the Tech Package, you're looking at ripping out the Navigation/Bose system to get EXACTLY what you want.
Yes, it's frustrating.
I'll try to sum up my story for you. iPod support is REALLY important to me and I've done a lot of research on this... it's best for you to really look around too.
I was considering buying the GT without Tech Package and getting just the stock radio - I was then going to rip it out and put in a custom aftermarket system. Part of me is sorry I didn't go that route because the Bose System lacks some really basic features in it's 6-CD Changer (like Pause, Mute, and a TRUE Random fuction). Of course, I didn't know that until after I bought the car WITH the Tech Package.
I DO *LOVE* the Smart-Key System... but honestly, would not have known the difference had I never had it!
So I'm considering, if an iPod solution doesn't become available soon (and a GOOD one, not a lame one) ripping out the whole navigation/bose system. Not a problem to me, but then for the "Tech Package" I'll have essentially paid for a moonroof and Smart-Key system. That's a lot of money wasted.
I had two car audio places, good ones, quote me about $2000-$2500 to do a really cool all-inclusive double-din system that would do Navigation with Live Traffic Reporting, Blue Tooth, Full-Speed iPod control, Satellite Radio and Rear Camera. This did NOT include amp or speakers, so it would be hooked to the existing Bose Amp & Speakers (which might prove to be a problem, but I didn't get further in my research because I decided to wait).
The head unit would be the Alpine IVA-W200 Double Din Version.
You can see a video about it here:
CNet Review
Crutchfield sells the unit -
click here
Keep in mind... places like crutchfield will list the unit as "not fitting" the CX-7. There is plenty of room for the unit but it's a hard install -- there's no dash/bezel kit or bracket kit available yet, so it's all custom. This is where a good audio shop will be essential (if you don't do custom car stereo work yourself). You'll want to research a place locally and really talk to the people working there. I'd also try to go to one familiar with Mazdas.
Another issue is the upper dash display. This area displays some basic information from the Factory/Bose Radio (like station, track number, seconds into the song)... currently there's no way to get an aftermarket radio to play nice with this display, so with any aftermarket system the area will become "dead" -- it will just show your clock on the left and climate control settings on the right - the center will always be blank.
A photo of the IVA-W200:
Alpine makes the best iPod capable radios because they offer a connection to your iPod called "Full-Speed" which makes scrolling through your songs and playlist almost as fast as doing it natively on the iPod. My husband has an Alpine system in his car with iPod support (not the one above) and it ROCKS. The iPod can be completely and intuitively controlled all through the radio itself.
A Photo (my husband's):
While the Smart-Key system is nice, and the moonroof is great, you have to decide if these two things alone are worth the cost of the Tech Package if you're just going to rip out the Navigation/Bose system. You'll want to haggle your ass off with the salesperson and get the lowest price possible. I've heard advice from "expert hagglers" that say to go as far as telling them you won't pay for a radio you're not going to use so the dealership should rip it out and not charge you... but I honestly can't tell you I've heard of ANYONE being successful doing something like that, especially with something like a Tech Package that includes Navigation. I didn't even attempt to go that route (maybe my mistake).
I've already decided at this point that if Mazda doesn't come up with the decent solution soon I'm going for the IVA-W200... but I am going to wait it out a little while longer... just be prepared, if you decide to wait also, to be a bit frustrated with the existing system. It sounds like music is important to you, and I can totally relate -- I LIVE by my iPod for music... and while MP3 CDs have been an okay solution in the meantime, the radio's other shortcomings have become obvious and aggravating (not to mention burning MP3 CDs is a pain in the you-know-what!). On the positive side, I do think the Bose System SOUNDS really good (best "factory" system I've heard, by far), the satellite radio works perfectly and displays channel, song title, artist, etc. on the nav screen, and MP3 CDs play great and display all song information on the nav screen as well... problem is, lack of Pause, lack of Mute, and lack of a truly good Random fuction are enough to make me want to pull my hair out some days... and I cannot believe an advanced system like this lacks such basic features!
I REALLY wish Mazda had thought this out ahead of time. A cool touch-screen system like they offer with the Tech Package could have easily accommodated decent iPod support if they had made it a priority.