Too true, but I think alot of the time, the only reason their re-writing wins them personal fame is because it confirms the hopes of a large number of people who want the history to be different. 

That being said ... I don't think there's much received, academic history thats actually been creatively invented. It's mostly just that perspective (which is subjective anyway) gets shifted, or that history becomes more selective - some events are ignored or downplayed, others are played up and exaggerated, etc. 

Pop history, well, that's a different story. Tons of stuff gets fashioned out of thin air there.

All of that really only applies to what I call competitive history, the "my ancestors were better/more important/stronger than yours" stuff. There's not much distortion or rewriting when it comes to the really specific stuff, like Aztec pottery or 18th century French farming implements because it's not competitive history. "My rake was bigger than your rake" just doesn't work too well.

Finally, its probably good to note that revisionism isn't always bad. Sometimes revisionism certainly does help to clarify things, especially when it's backed by solid, straightforward evidence. A good example: the discovery of L'anse Aux Meadows in Newfoundland. But it's always correct and right to be skeptical when the evidence is less than solid. It's a rare few that happen to get it right.