While Nintendo’s spokespeople mostly avoided discussing DSi software last week at E3, at least one new game has been released on the online store every week since the system launched. A handful of those “games” are calculator and clock applications, but there have been a few first-party gems along the way. In particular, Pictobits and Mario vs. Donkey Kong: Minis March Again! are absolutely worth the asking prices of $5 and $8, respectively. Neither would work as tangible, boxed products, but they’re just about perfect for the DSiWare service.

Pictobits is the latest game to be released under Nintendo’s “Art Style” banner. As I mentioned last month, Aquia, the first DSi game in the series, was the best launch title by far. Pictobits continues the trend of excellence with another unique take on the “Match 3” puzzler. In this installment, you have a “well” to store multicolored tiles, and you need to strategically drop these tiles under falling shapes to clear them. However, these shapes usually come down in clusters, forcing players to figure out the best order to clear each one. The result is a bit more cerebral than something like Tetris, but without sacrificing the manic pace of the best puzzlers.

Once you clear tiles, they become “bits” on the top screen, eventually forming a pixilated 8-bit character from Nintendo’s cherished stable. The standard Mario and Zelda iconography is here in full force, but some obscure Japan-only games make cameos as well. Better yet, as you clear shapes, you’ll be rewarded coins that can be used to purchase chiptune remixes of NES soundtracks. If this game were on store shelves, I’d bemoan this as a cheap substitute for additional game modes, but at $5 the unlockables are icing on the cake.

March of the Minis isn’t quite in the same league as Pictobits — it’s Lemmings for Dummies, minus the green-haired rodents — but the sheer volume of content is nonetheless impressive. The download packs dozens of levels, collectable items, and a level editor. Better yet, you can share designed levels online. The Youtube-style rating system ensures that at least some of the best levels will rise to the top, meaning that March of the Minis will last as long as you want.

Unfortunately, for all its bells and whistles, March of the Minis doesn’t quite click when it comes to the actual action. Though the first Mario vs. Donkey Kong (and its beloved ancestor, Donkey Kong ’94) gave players direct control over Mario, the miniature robots in this third outing can only be “steered” by placing blocks in their path. This is easy enough to do using the stylus, but the final product feels too passive. For the first half of the game, you’ll rarely need to do more than place staircases and walls, and the challenge doesn’t kick in until the post-game “plus” stages. Still, it’s much easier to recommend than its full-priced predecessor.

March of the Minis is also significant because nobody had heard of it until Nintendo announced it a week ago. The company is notorious for withholding release dates of WiiWare and Virtual Console games, but I was still surprised to see a major release so suddenly unveiled. While there’s nothing of interest on the the DSiWare horizon at the moment, this recent development gives me some hope.