I have tested the google voice to text on several ccok roms - all work perfectly , just make sure is ver 2.2 Froyo. The voice to text needs some not much practice. Speak slowly ; even if inaccurate the phone will prompt you with closest options. My sms dictation.call contact/upload to Facebook  is close to 100 % accurate . When talking, pace yourself and you will soon get it right. I managae to hit accuracy after less than 10 tries. Your surrounding must be quiet , so not so practical in busy places like cafe, on the road . Tried inside car , still ok but need more edits on the words

The latest google voice actions is a big leap forward

Perfect your voice to test on sms, email, navigation,etc - then demo to your iphone friend s- let them "die with envy"