I wasn't very excited either when I opened a Shards of Alara pack and found little old Flameblast Dragon staring back at me.
Flameblast Dragon is confirmed to be in the new core set. There is a lukewarm response so far, which is only understandable since our scaled friend is just plainly good and certainly not overpowering.
Here are some quick observations I had about Flameblast Dragon.
1) You can tutor for him with both Ethreal Usher and Netherborn Phalanx.
2) He is repeatable removal. Flameblast Dragon switches from the traditional red mana pump of Shivan Dragon to essentially a triggered Blaze ability. Or in Revised-speak, "Not-quite Disintegrate and not-quite Fireball". He can target creatures or players (or planeswalkers!). His ability uses mostly colorless mana, perfect in a world of cheap artifact mana and often multicolor mana bases.
3) The ability is triggered by him attacking. But it works completely independently of the Dragon's combat phase. The ability happens before blockers are declared, so you can roast a defending creature before it even has a chance to block. Of course your opponent can always just choose a different creature, and if he has a load of 1/1 flying tokens he will be able to chump block you.
4) On the other hand, chump-blocking is somewhat ineffectual since he can use his ability to roast your opponent directly.
5) Finally, in multiplayer games Flameblast Dragon can attack the most defenseless player at the table which simultaneously roasting the defenses of the most protected/threatening player. This seems very powerful to me, with the only negative aspect to consider being the tapped dragon at the end of your turn. You will need some type of defense when retribution comes.