Some say that the Metroid Prime games doesn't live up to standards set by earlier games in the venerated Metroid series. They might have become bored with the backtracking and fetch quests that plagued Prime 1 and 2, they might have disliked the use of the 1st person perspective, or maybe their views on the games, which are almost universally seeb as masterful by critics, were tainted by nostalgiac memories of their 2D predecessors and a purist vision of how the games "should" play. Irregardless of their reasons, Metroid Prime 3 is surely a much easier game to swallow. It remedies many of the quibbling flaws from the first two Prime games including:
-Useless trekking through areas that have little to no remaining importance simply to reach areas that contain "artifacts" or other upgrades of significance. This was solved through transportation via Samus' ship from planet to planet, and slightly smaller areas that are much quicker to navigate than the single, massive worlds of Metroid Prime and Metroid Prime 2.
-Controls that were arguably substandard. Metroid Prime 1 and 2 utilized a lock-on aiming system that was a bit boring and slow in comparison to first person shooters, but was much more conducive to the platforming that is a staple of the Metroid series. For Prime 3, Retro ditched this method in favor of a more traditional FPS control scheme that, at the very least, is more accurate than any other console FPS, and is the new benchmark for FPS controls on Wii. Aiming is intuitive and very fun now- you'll probably want to adjust the settings first though... expert controls are the only worthwhile option. Also, the platforming still works just fine.
-Backtracking is simply made more tolerable. Most of the artifacts that must be collected to finish the game could easily be found without actively seeking them, which makes the end-game search quick and painless.
Other than that, MP3 makes novel use of the Wii remote for short, motion-sensing puzzles, which makes it feel all the more like it belongs on Wii. Players are asked to twist the remote to open locking mechanisms, and flick the nunchuck to grab enemies or attach to grappling points with Samus' grappling beam. Later in the game, players repair circuits in a sort of blow torch puzzle that uses the IR pointing function of the remote.
Small improvements were made to the already magnificent engine from Metroid Prime 1 and 2, most of which are related to lighting. The textures sometimes looked mangled on my LCD TV, but I haven't played any 480p Wii game that doesn't have some rough spots when upscaled to 720p. Despite Wii's lack of HD prowess, some areas are amongst the most beautiful, immersive environments (one is actually reminiscent of Cloud City/Bespin from Empire Strikes Back) I've ever seen in a videogame. And the music, just like in previous entries in the series, is melodic and often tranquil.
Altogether, Metroid Prime 3: Corruption is a bright spot in a mostly barren Wii software library. Even if you are only accustomed to playing Wii's "casual" games that require the user to do little other than sit there and swing the remote every once in a while, I highly reccommend you to give this amazing game a chance.
Update On Jun 23, 2008: In haste to publish my review, I forgot to mention a few details some might find useful. For one, this game is 480p and 16:9 compatible, which is good to know for HDTV owners.
More importantly though, and I should've said this more explicitly in the original review, much of the gameplay consists of acquiring new items and item upgrades through explorations, then deciding how they could be used to unlock new areas in the world. For instance, a missile might unlock a different type of door or destroy a mass of rubble blocking a pathway, or an ice beam might allow you to access new areas by creating frozen platforms in pools of lethal substances. It's addicting, and requires you to think perhaps more than any other FPS.
Update On Jun 23, 2008: Wow, I never really touched on the corruption element either. At the beginning of the game, Samus is corrupted by phazon, a dark, ethereal substance. Her suit takes on new features, allowing her to become much more powerful at the cost of her own vitality. This "hyper mode" is put at the disposal of the player, and can be activated at will at the press of the + button. Surprisingly, this adds depth to the combat, forcing them to choose when they should use it wisely. If they use it too long, they run the risk of losing health, but if they don't use it enough, they'll be clobbered by the game's formidable bosses and hordes of space pirates.