Over the past three days, the comet Holmes has brightened from a 17th-magnitude to around a 2.5 magnitude brighteness: bright enough in fact to be seen with the naked eye. According to Sky & Telescope this isn't unprecedented; this is how the comet was found to begin with, 115 years ago.

As of tonight the Sky & Telescope article has an update:

Using Alpha and Delta Per as comparisons (magnitudes 1.9 and 3.0), MacRobert estimated the comet to be magnitude 2.8, just a trace fainter (more similar to Delta) than two nights ago. In stabilized 10x50 binoculars it looked just the same as before only bigger, with all its salient details easier to see.

I'm no astronomer, but that all just sounds weird. This thing flares up by an insane amount and although it has stablized in brightness, its features are just getting bigger... sounds like its headed at us, heh.