Presentation and Gameplay
"Mario and Luigi" starts with Princess Peach traveling through time to visit the Mushroom Kingdom of the past and, predictably, being abducted. Instead of Bowser, however, a new threat arises from the villainous Shroob aliens, who are attempting to take over the world. Mario and Luigi are joined by their infant counterparts. Like "Superstar Saga," the face buttons of the DS control each individual player and the unique team-up moves help the player access new areas and combine strengths in battle. Enemies, which can be counterattacked and avoided through well-timed button strikes, will often fly to the upper screen of the DS during their attacks and must be carefully scrutinized.
Surprisingly, the DS iteration looks only slightly cleaner and more polished than the GBA version and with a single (spoiler-ish) exception, doesn't utilize the technology of the DS at all. More disappointing, the storyline, which relies heavily on time-travel, doesn't allow the player to explore the past and present versions of any of the areas in the game, except the main castle which serves as a hub world; the opportunity lost to see past and present versions of notable Nintendo characters or to explore transformed areas hangs over the proceedings.
Music and Graphics
A rarity, the music in "Mario and Luigi," written by the legendary Koji Kondo, is absolutely forgettable. Even now, twelve hours after putting the game to bed, I can't remember a single theme but I can readily recall several from "Superstar Saga." While playing, no single theme stood out as being incongruent or dissonant with the environments, but to proclaim a Kondo soundtrack as being forgettable is a rather high insult. Craig Harris of IGN wrote that "Mario and Luigi intentionally speak gibberish, but it works well with the story. The game's soundtrack fits the Marioesque theme with original pieces and remixed classics." Although that's all true, it again merely echoes the previous games in the series and relies more than typical on nostalgia.
Like the music, the graphics, as noted above, don't do anything to expand on the horsepower of the GBA iteration, content to simply polish a few rough edges and import much of the sprite design and palatte of the original. The failure to incorporate any of the technological prowress of the DS feels like another missed opportunity.
Conclusions
Expanding a valued property such as the "Mario and Luigi" series on Nintendo DS that historically incorporates ingenious combination attacks and light RPG trappings was, and is, a no-brainer. Although even the worst Nintendo games are often light-years ahead of the competition, "Partners in Time" doesn't do quite enough to expand on the existing formula to make it a must-play although it's a cute, and enjoyable weekend for anyone looking for a good game.

What would you rate this game? It was very cute to watch! I'm sorry that it wasn't fantastic, but glad that it was a nice, concise game. Love you!