I've just updated the firmware on my Samsung. It IS disconcerting that there is no explanation as to what issues the firmware addresses or what to look for, but here is what I've found this evening since updating the firmware:
1) Start-up time appears to be faster. I tried Sony, LionsGate, and Warner discs and they all seem to load the menu or logo screen in about 6 seconds, give or take. Also note that the hourglass is gone, replaced by the colored dots described by some on AVS forum on the units that have been modified.
2) DTS and DTS-ES playback on Blu-ray discs no longer cause stutter. I gave both Crash and T2 a test drive. I had seen Crash look jumpy when using the DTS-ES track before and switched over to Dolby Digital EX. However, I am happy to report that is no longer necessary for DTS fans.
3) 4:3 SD segments played back on BD discs now are presented in pillar-box. Before the update, the standard-def featurettes on Warner Bros.' Corpse Bride played back stretched to fill the 16:9 screen. Not so anymore. SD plays back in the appropriate aspect ratio. Side note: This correction does not seem to apply to SD discs.
4) Standard DVD up-conversion greatly improved. Previously I steered away from using the Samsung to play standard DVDs, using instead my Toshiba HD-A1 HD DVD player for its excellent up-conversion capapbilities. The Samsung is now in the same ballpark! The once fuzzy clumsy up-conversion process has been bumped up to a respectable quality. I have not yet done a side-by-side comparrison, but suffice to say I no longer see the need to avoid this player to up-convert my SD DVDs now.
There may be other changes, but these are the ones I've noticed so far. I did notice there are actually 3 individual files in the firmware update, so I'm thinking that represents 3 individual functions of the player that have been specifically addressed.