If the mention of "Poland only" in the title didn't deter you, you'd probably like to know that, hot on the heels of the LG G3's Poland-only Lollipop update, Samsung has decided to begin its Lollipop update for the Galaxy S5 in that country as well. As for what's new, you obviously get all the new goodies that Google has included in the OS, as well as some fairly substantial visual changes to the look and feel of Touchwiz, including a material redesign of some core Samsung apps.
The new version number is G900FXXU1BNL2 and is based on Android build LRX21P. The SM-G900F is the worldwide, unlocked model, so chances are good that we'll see this update roll out to more countries soon. As for when US models will get it, I wouldn't even begin to speculate. If I were a betting man, though, I'd take the "over" on January because carriers.