After I heard about this, I've been running ways in my head on how this can become a good film considering its being done by the producer of Eragon.
First, we can be asured the effects will be great. Eragon looked fantastic, Saphira was very well done. Plus it should be all CG considering the only thing even close to humans were the apes and Hunter's race.
Second, A original story. The writers won't be limited to a book and can branch out in there own paths as long as it stays within the Spyro world. This is what killed the Eragon movie, too many people comparing it to the book and were disappointed.
Third. A pre-set cast. With the exception of 2 characters, every character has been played by the same actors in all 3 games. The movie would be beyond insane not to use the cast from the games. This also opens the door to get some other big names in the list. Heck, actors perfer voice acting over real acting anyway, much easier for them.
Fourth. Warning: Do not highlight unless you've finished the game. The ending of the game left the door wide open for further adventures with the new age beginning, both Spyro and Cynder admitting their feelings, and Ignitious taking on the role of Cronicler.
All in all, I'm look to it with hope.