I became acquainted with Marcin Wasilewski's trio through Tomasz Stanko's albums. The music they recorded is easily some of the finest stuff released by ECM (or at all!). Even though Stanko is a fantastic musician in his own right, I was incredibly excited when I saw that the trio was branching off to do their own thing. Their pre-ECM records are very good, but the recording quality wasn't quite the same as on ECM efforts, understandably. Their first ECM release, "Trio", took care of that and was a great record. "January" was even better, continuing the line of musical thought established in the trio's previous releases and polishing it. "Faithful" is their best record yet.
If you enjoyed the Marcin Wasilewski Trio's previous efforts, pick this one up without any second thoughts. If not, I recommend buying all of the ECM releases from the trio. The music is sophisticated yet accessible, with plenty of interesting melodies, happenin' improv, and tasty harmonies. I suppose you could knock these guys for "not evolving", but who cares when the music is good in the first place? No other piano trio comes close to these guys, and I for one can't wait for their next release.