One question. Will the mic in the link work with this camcorder?

Panasonic MIC150 Shotgun Microphone for HMC150 & MIC150 B&H

Yes. But it's not a very good mic. Any XLR mic will work on your AC90. I recommend the Rode NTG-1 or NTG-2. It's significantly better for only about $70 more. You can also use it on a boom pole pretty effectively.

I guess I just went by the reviews that people said.

Hi Scott

I found that even the Rode Videomic worked really well on my Panny HMC cameras and later on the AC-130's ... I do weddings and in noisy areas and the Videomic has enough punch to give you decent audio. However it is a 3.5mm plug so you either need their mini jack to XLR adapters or what I did is simply rewire the mics with new cable and an XLR plug. Just remember that for some strange reason Panasonic never put any auto gain circuitry on the XLR channels on the AC-90 so it's all manual!! I have no idea why as all the HMC camera series had auto gain for the XLR's and at events it's almost impossible to keep up with rapidly changing ambient sound levels!!!

Chris