This started when the new block formats were introduced^{so it has been here for a few snapshots}

Fire isn't bright anymore like it used to be.
take a look of the pictures
It's more noticeable on greater distances

I already put together a resourcepack to fix this bug and it's found on the attachments.
(btw. HOLY hell it was a pain in the ass to make! Lots of maual copy-pasting effort was put in...)

The Light_fix_Extra fixes the fire bug AND gives torches, sea lanterns, glowstones and redstonelamps some more glow!

The Light_fix is the sripped version with only the fire fix

I hope that Mojangstas see this!