Judging from the comments for the recent review of Armor Picross 2, it seems that many in the JIG community really like picross, and I do, too! Sometimes I'll delay working on economics homework just to play a game (or two or three or four) of picross. And there are so many online implementations of my favorite game, and all with a different interface. So, which one to choose? For some, the question may be difficult to answer. But not for me.
I choose Picture Logic from Isomura Kai (TONAKAI interactive), developer of the previously reviewed Out File #1 and #2 escape games and the arcade game, Rapture Capture. So far, Picture Logic is my favorite implementation of picross (aka 'nonograms' or 'fill in squares with colors'), and the interface is simple: Click once for a color square, twice for 'X' square, and click again to clear. Plus, you can click-drag to quickly fill in those pesky lengths of boxes. My only complaint is that playing on a laptop can really cramp your fingers.
Each puzzle will show you the percentage of people who solved the puzzle, so you have a rough guide of puzzle difficulty. Lower percentages means harder puzzles, so watch out beginners! Some nice extras: When you finish a puzzle, the game will save your progress and checks it off!
The site is in both Japanese and English, but unfortunately the English portion is quite lacking. To get the full picross experience you will have to look at Japanese words. There are almost 200 puzzles now, so you won't finish them all in one go (unless you are addicted to picross and cannot stop playing). There is also something for creating your own puzzles, but because I can't read Japanese, I cannot help you there.
All things considered, if you love picross puzzles like me, you owe it to yourself to
Do you have a favorite site for picross? Please don't post a link to it here in the comments, submit the link (or even your own review) using the "Suggest a Game" link in the menu above, instead.