I hate it.
I particularly hate it if the writer uses it to make a poor (sob), suffering (sob), universally despised (sob) cadre of magicians, who, despite their sterling character, are dumped on by everyone else, but I hate it even when your magicians are well-respected.
Unique, freakish abilities, not quite under control, work, but not magic in general.
Tolkien's wizards are not as bad as the general run-of-the-mill trope, because they weren't human; no one who's human can do magic in LOTR. Even Aragorn, with his healing hands, has just a drop of non-human blood (being Elrond's great-to-the-nth-grandnephew). Still I think they were a bad influence. Sure, there are people who practice magic and people who don't in Sword & Sorcery, but I've never read a work where this was a difference in kind. (Gray Mouser, for instance, even knew some magic.) And in early fantasy, folklore, legend, and myth, either you weren't completely human, or you did something that everyone else could -- in theory -- do.
Much as I like Harry Potter, I prefer a setting like Operation Chaos, where you have magic in the modern world and everyone knows.