Deftones are a totally different entity to Opeth... you can't think of one in comparison with another. The musical ideal is entirely different. Deftones are an excellent band. While they may not posess the jaw-dropping musicality of Opeth (who does?!?!), they create dark, dense atmospheres, that communicate something just as worth while. White Pony is a superb album, perfect atmospherics (great Maynard James Keenan cameo too), and all of their albums have something to offer.
As far as them being a nu-metal band is concerned, this IS true, to an extent. However, it depends on how you look at the concept of nu-metal. In the true sense, nu-metal developed in the mid-90's as an agressive, depressive alternative to the cliched mainstream American metal scene. There were two pioneering band, leading two different paths. One of these was an exciting new musical wave, where emotion once again became the forefront of the (American) scene. This was the path led by Deftones. The other path was the one which became prevolant. It was pioneered by Korn. To this day, it horrifies me that Korn attained such freakish levels of popularity.
Also, Chino Moreno is one of the most emotive vocalists going, and he communicates feeling through his words in a way most singers just... can't. Mikael Akerfeldt and Jonas Renske are two of a VERY small number who can match (or outdo) his ability to put across feelings through song. Jonathan Davis, now HE sucks....
