With Final Fantasy X, Square finally loosened up on the incredible weight they laid on Uematsu's shoulders with previous installments of the series, accumulating in the unsurprisingly stretched Final Fantasy IX Original Soundtrack, which had so much music it didn't even fit on 4 discs.
This time around they decided to let Uematsu spend more time doing what he does best, while injecting necessary freshness into the series in the form of Junya Nakano and Masashi Hamauzu - a choice which did nothing but good to the series. Their contributions to the soundtrack were significant, resulting in not only a new sound, but also some extremely enjoyable and memorable tracks. Hamauzu's work on the album are most obviously presented in his arrangements of the Song of the Fayth tracks alongside Uematsu, but the focus he put into the entire Bevelle sequence - from Start to Attack to I Can Fly, along with the crazily complex piano concerto, Decisive Battle, prove that he's right up there with anything Uematsu could hope to produce. Nakano, on the other hand, seems to dwindle more in the shadow of this soundtrack, where he focuses more on the darker and faster tracks, of which Hurry!! and A Contest of Aeons are perhaps the most noteworthy. But these too were obvious requirements to add to the dark atmosphere of places like Baaj and Macalania ingame, so even his input helps add an extra dimension where Uematsu faltered.
That said, Uematsu managed to put forth an incredible work even with out of date implementations such as Revealed Truth or the almost hilariously cheesy Fight with Seymour - as with most of his works, even Final Fantasy X has a sort of musical plot twist going on for it with the amazing Otherworld, and the Song of the Fayth and Suteki da ne themes are undisputably part of what is so memorable about Final Fantasy X's musical score.