Yeah, for all effects you are considered a dragon and a member of your original race (which was dragon, too).
That's nice. That's actually exactly what the dragonblood subtype means. It still doesn't change that, by the rules, you're Humanoid (dragonblood) when you go dragonborn. Now, mind you, I'm not opposed to houseruling you keep your type, but I just wanted to point that out ahead of time.
Dragonborn is contradictory. It says you keep your original type, which is not restricted to being humanoid, but then also says you are a humanoid (dragonblood) afterwards. It is obviously a screw-up on the author's part, and is basically unuseable as written for non-humanoids, as it is impossible to both keep your non-humanoid type and also be a humanoid. You only have one type. It can't be both ways. So it in fact
requires a houserule to even use it on a non-humanoid.
It is also obvious that the author's were just writing from the perspective that most creatures taking the template would be humanoid (as most PCs are), and weren't careful in their editing/writing in considering what happens when you add it to a non-humanoid. So saying that you keep your original type and gain the dragonblood subtype is the most logical way to interprete/houserule it, and I'd say the RAI. If you don't do that, you have something that is both a humanoid and a non-humanoid at the same time...
Edit: Strat, my character in the "robot" game is a dragonborn warforged. So you've already approved the template.
I assumed that his type stayed the same, for the reasons I outlined above. You can look over the "template" online:
http://www.wizards.com/default.asp?x=dnd/iw/20060105b&page=1 (it says it is a race, but it works more like a template. I think whoever wrote this had their head up their ass.)