My grandfather's name was Bamlet Rumford, and his family is listed in the 1911 Canadian census records. Except several transcribed records list him as Hamlet Rumford. Now, that's not a huge error and wouldn't likely trip any genealogist up. But it's just one example of how errors can be made when people are trying to read these old records. The original does say Bamlet.
So make sure to keep that in mind when using census records. Especially when you have relatives whose names are unusual, or just aren't spelled in the traditional way.
Oh, and if you do find an error in an online transcription record, see if you can contact the people doing the transcription and let them know of the mistake. I've had a few sources change Hamlet back to Bamlet so far. But only do so if you are positive of your information. No sense adding more mistakes to the records.