I'm pretty cheesed that the VX6700 doesn't support SDHC cards, thus limiting me to 2gb storage capacity. Is there any chance that the manufacturer will update the firmware in the near future, or will they make us upgrade our phones in order to get larger capacity?

At this point we don't even know if it is something that can be updated via software. The Sandisk site says that SDHC cards are only compatible with new devices designed to accept them.

I was under the impression that the only difference between the two was that SDHC supported Fat32.

I'm sure this was just a typo on your part. But the Verizon one is the XV6700. The VX nomenclature is for LG branded phones. BTW Welcome to the site!

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XV6900 Custom WM6.1, 8GB microSDHC
History:WM6.1 XV6800w/GPS,XV6700 WM6.1,Samsung i760,Moto Q9m,Moto Q,XV6700,VZW Treo 700WX, Treo 700W,Samsung i730,XV6600,Treo 650,Treo 600,Kyocera 7135

I have seen some rumors posted of a new ROM upgrade for the Sprint PPC6700. Does anyone know if this is true? This would be the second upgrade for the PPC6700 and it seems unlikely to me. Does anyone have any information?

Check out this thread (read it all the way through), it looks like these guys have had success with getting the 4 Gig mini sd to work.

But not SDHC cards, so you'll be limited to 4gb. But let's face it 4 gigs ain't bad.

What's to say that a future non-SDHC card won't support capacities higher than 4gb? Or is that impossible, technically?