Do the Garmin gps units with cameras take video as well?

Smartphone. The camera will be much, much better, and the video will be much better too.
The HTC One X, the iPhone 4S and the Samsung Galaxy S3 (whenever it's released) will all work substantially better. As far as I can tell, standalone GPS units, except in certain circumstances, are obsolete.

Do standalone GPSes get better reception?

Do smartphones lose acquisition worse in canyons?

What I want is a unit that is good reception GPS, camera, and can send and receive text via satelite

I have an Oregon 550. It does not do video. Even if it could, there's no microphone to record audio. I wish it could because I'd use it to record audio journals, and maybe shoot some video too.

"In certain circumstances" is the key phrase. Smartphones can be great GPS units, but my iPhone is not about to replace my Garmin Montana. It's too fragile and the battery doesn't last nearly long enough. The GPS function is largely (but not completely) inferior to the Garmin… acceptable but not great.

Yeah, that's why you don't use an iPhone ;)
Who thought making a phone entirely out of glass was a good idea? And then giving it a non-removable battery? When I use my phone in the backcountry I carry a couple extra batteries. Minimum weight penalty to know I'm not going to run out of battery.
The actual GPS function has always been plenty good for me. Not perfect, but I also don't rely on it.

I've long dreamt of a device that functioned well as a phone, camera w/video & audio, and GPS, but was somewhat rugged and used removable AA batteries. Some upcoming phones with Gorilla Glass v2 should do the first part okay. It'd do the latter part well too if they engineered a removable back that permitted AA batteries. Now I'd also love a high resolution screen that's viewable in direct sunlight with low power consumption. Call it the device for adventurers.

You might want to verify whether your smartphone gives you proper elevation. My iPhone 4S does not calculate elevation from the GPS signals. Instead, it looks up 2D data on a topo map to report elevation which is not the same thing.

A simple test is to look at your elevation when you are on a bridge. Does it report true elevation or ground level under the bridge?

You may not think this a big deal unless you are trying to find where you are on a steep hillside or down a steep ravine. The accuracy of the topo is also a big question mark. Waypoints I have taken with both dedicated GPS and iPhone do not always show up in the right spot on Google Earth for example.

For anybody using an iPhone it’s important to read the battery conservation section in the article: Instructions for using iPhone as Backpacking GPS/Mapping device.

The iPhone does not have removable battery, as others have said. However, there are some important things you can do to preserve battery, and there are small light external battery rechargers. Using the battery conservation measures, I’ve used mine for 4 day stretches without recharge, and AlanD has used his on 6 day trips.

The mapping/GPS apps for the iPhone are great. I’ve used it is my primary navigation tool on three six-week trips in the past year to places where good paper maps are either unavailable or super expensive (Turkey, Australia, Spain). For a $10, you get track and waypoint management, downloadable maps and satellite imagery of the world, etc etc. If you’ve got an iPhone (or Android too), then it’s worth the investment to give it a try.

Good luck, AmyL