Does an iPhone (or iPod) charge as just as quickly when plugged into a computer?

nope you can charge in like an hour or so faster with an outlet

Logic would say that the wall charger would be faster since it's not syncing and the sole purpose is to charge.

Well... i'll just plug that sucker into the wall then!

a sleeping mac will drain an iPhone battery. No joke. It's in the support literature.

strictly speaking, a sleeping mac doesn’t drain the iphone battery, it just doesn’t charge it. so your phone sits there, switched on, not charging. this is because the mac cuts power to the usb ports when it sleeps to save electricity.