One of the advantages of iPhone 4 over most Android-based competitors is 720p video recording. Now an older but still very popular Android smartphone, Google's Nexus One, gets that feature -- albeit by means of a hack.
Although not officially supported, this "feature" makes sense given that Nexus One's camera is one of the most advanced cameras we've seen on a smartphone.
You must run Cyanogen’s CM5.0.8test3 software, which unfortunately means that Android 2.2 (Froyo) is not supported. The full procedure to enable 720p video recording on your Nexus One is detailed here.
Future updates to the hack should include Froyo support, as well as better video and audio quality. Check out a very short sample 720p video, recorded with a Nexus One, below.