Now that I've gotten comfortable with PhoneGap's command line I'm finding myself much more productive when building quick demos. The previous link will tell you more, but as a quick example, this is how I'd quickly dump out an IOS project.
"ioscreate" is not the name of a PhoneGap binary, but simply a symbolic link to the create binary from the PhoneGap iOS directory.
I then CD into the folder, run "subl www" to open the www folder in Sublime, and run "cordova/build && cordova/emulate" to run the build and emulate commands. This pops open the new application in my iOS simulator.
All of this takes about 2 seconds and works great, except for one small nit. By default, the new project has this fancy HTML.
You can't see it - but the green "Device Is Ready" is pulsating. It's very hypnotic.
Luckily there is a quick fix for this. Given your desired platform, go to where you installed PhoneGap and you will see a "bin" folder and beneath that, a "templates" folder. There should be one folder underneath it.
See the www folder? Just edit the contents within there to your liking and the next time you create a project, your modifications will be used. Here's my version.
Ok, that's kinda boring, but I've got a nice blank HTML, JS, and CSS file ready to go in my editor.