I have a microSDHC for a underwater camera. The price difference between SDHC and microSDHC isn't that much. You can get up to 32GB micro SDHC. Which is the max memory that my underwater camera can support.
Just nice to have a microSDHC if you buy a device that has a microSD slot.
I'd prefer a Micro SDHC over a standard SDHC b/c of flexibility.
You can always use a Micro SDHC in a regular SD slot with the adapter. So a Micro SD card is more versatile, and with more and more CELLPHONES coming with Micro SD slots, you could always move the MicroSD card to a cellphone down the road, besides obviously SD cameras, etc.. The fullsize SD card you're more limited on what devices can use it. (ie: Cameras & computers)