I've watched most of the games so far in this year's playoffs... which, btw, has been one of the best playoffs in recent memory, in my honest opinion...
There's always the big-name stars like Kobe/'Melo/Billups/Howard/LeBron that are performing as expected, but there's been some impressive play by other guys that I thought deserved mention:
Mickael Pietrus (such solid play on both sides of the ball; wish he had been a part of the GS trade, lol)
Turkoglu (when he's on, Orlando is extremely tough.. needs to address the seldom spurts of wtf plays)
Rashard Lewis (such versatility, seems to have stepped up his game quite a bit for the playoffs; his shot is so unorthodox, but so effective)
Courtney Lee (impressive for a rook, seems unfazed by playoff basketball)
Trevor Ariza (clutch defensive stops, he makes championship-type plays)
JR Smith (his shooting stroke beyond the arc is freakin gorgeous)
*notice the number of Orlando players on that list* (then realize they also have a guy named Dwight Howard, who's just doing his normal thing)
As a side note: I feel like the two best teams top-to-bottom in the playoffs have been Orlando and Denver... although I'm sure the league would love a LA/Cleveland matchup to showcase Kobe/LeBron.