This card isn't really that bad. Giving something flying for 2 mana is pretty good, but it does go down for 4, so it does require a steep investment fairly late in the game. Also, it does have to tap to give something flying so it only works on one creature (Power Matrix also taps, but it gives a multitude of effects). If it didn't tap, it would be much better (similar to Predator, Flagship).
Now, on to the other reason I chose to review this card today: its errata. Above is the Fifth Edition version of the card and below is the Sixth Edition.
Now, the removal of the sack trigger did make the card better, but why did they do that? Flavour-wise it makes no sense: if a guy dies on his flying carpet, his carpet will probably get destroyed too. Such a radical shift in card wording is odd to see outside of single-printings of cards.
Pros: Gives a creature flying for cheap, wording change got rid of sack trigger
Cons: Initial cost of 6 to get going, only affects one creature
Replacement: Power Matrix