In the intro theme, most of the cars in the background are newer then the set time period. About halfway, you see an at least 1997 Ford F-150 pickup drive by the left windows, not manufactured yet.
The show was originally titled "Teenage Wasteland" or "The Kids are Alright" but those were songs by The Who and, legally, Fox couldn't get permission to use them. They renamed the show "Feelin' Alright" to show the focus groups. However, nobody really liked the name. After the focus groups airing, the audience were heard saying they really liked that show about the 70's or that 70's show - and the name stuck.