By default, the iPhone 4 can only upload video in standard definition, which makes sense for those using 3g, but the same limitation applies even when you are on WiFi.
If your wondering how to upload those beautiful 720p videos from your iPhone 4 to YouTube or any other website, then check out PixelPipe HD. It supports basically every major service, from Dropbox to Twitter and everything in between.
Liberate your media with Pixelpipe and get your media off of your iPhone and out to your favorite social network, micro-blog, photo/video and blog services. With over 110 supported destinations from around the world to choose from the choice is really yours. Free your media and share your life.
The app allows you to queue various media to be uploaded in the background, and supports files up to 225MB. When choosing what media you want to upload, you can “tag” the site you want it to be uploaded to, so adding @photobucket and @facebook will upload the file to both. It is extremely robust, and you can even select what album you want to file to go to, so it’s not just blindly uploading it.
PixelPipe is free, and works with the iPhone and iPod Touch on iOS 4.0 or later.