When I was updating my ipod touch 4g 8g 4.3.3 the USB came out and now it just shows connect to itunes and when i try to update it comes with error 6. I do all of the help things and nothing
First see if placing the iPod in Recovery Mode will allow a restore.
Next try DFU mode and restore.
How to put iPod touch / iPhone into DFU mode « Karthik's scribblings
If not successful then time for an appointment at the Genius Bar of an Apple store. You are not alone with this problem.