I really do like this list of the top fifteen fascinating exoplanets
an awful lot. Not only for the pretty pictures (although they are awfully seductive) and the neatly encapsulated biographies (although they do contain some neat and startling stuff), but also because it shows how much we've learned since the first exoplanet, 51 Pegasus b, aka Bellerophon, was detected in 1995. As of this date, we know of some 429 extrasolar planets
. They orbit main sequence stars, red dwarfs, binary stars, pulsars. We know of several stars with more than one planet - solar systems like our own. Most are the size of Jupiter and many orbit close to their parent star, but that's not surprising, given that current detection techniques favour finding that kind of planet. But as the list shows, there's enough variety to begin to create a rudimentary taxonomy of planets in other solar systems, and to understand how they formed and what they might look like.
And I'm especially interested in that, because I'm writing a novel set in and around planets of a particular nearby star, and I'd much rather have some data to ground my speculations than make up stuff out of whole cloth. When I started reading SF, in the 1960s, there were an awful lot of stories set on alien planets, but the planets were all much the same. They were all mostly habitable, all mostly extreme variations on Earth's geographical, climatological and ecological features; only a few writers, notably Hal Clement, Poul Anderson, and Larry Niven, tried to create wholly exotic yet believable alien worlds. It's a very different game now.