I'm using Simcraft on its PTR setting, which SHOULD take the 4.1 changes into account.
Just did a 10k iteration sim of a 372 BiS Frostfire mage, and went over the results. Then did another test using the same character and spec, and the live version.
On the live version, Ignite uptime was 97%, with an average tick of 7.9k and a minimum tick of only 140 (Probably a Frostfire Bolt tick crit). On the PTR version the uptime was less, 77%, but the average tick was up - to just over 10k. So Ignite uptime was still fairly high, and the average damage was up - minimum tick was 840, which I imagine was an ignite from a Flame Orb crit, which I believe is not counted as a DoT.
So, it looks like Simcraft IS correctly modelling ignite with the new 4.1behaviour, and Frostfire bolt is therefore still worse than Fireball.
Interestingly, the damage of Frostfire bolt specs in 372 BiS gear with a normal crit / haste focused gear setup was more than a mastery focused one. Which seems to go against the theory that some had that a mastery focused setup with FfB might outperform Fireball. Well, it still might, but it might take massive levels of mastery to achieve it - with reforging and gemming prioritising mastery, I ended up with 17.3 mastery, and it was almost 200 dps lower than with a crit / haste focused setup.
So, it looks like, at the moment, Fireball will still be the way to go with Fire specs in 4.1.
Origin ID: Slashylol
Steam ID: Wargod37