Shiver by Maggie Stiefvater

If you loved Twilight, then Maggie Stiefvater's Shiver is a book for you. It's got plenty of sexual tension between teenagers from two different worlds - Sam is a shapeshifting wolf/human and Grace is human. The setting is contemporary and realistic: Mercy Falls is a small town bordered by wilderness in Minnesota. Grace is stoic and dependable, which maybe doesn't sound so appealing, but I liked her better than Twilight's Bella. She falls in love with Sam when he is a wolf and commendably maintains her attraction to him when he is human. (This steadfast romance is the part I found over-the-top, but that's just me.) Sam has gorgeous golden eyes, the only part of him that looks the same no matter which species he inhabits. He is rather a cautious sort, letting Grace take the lead much of the time, which makes him more like Jacob than Edward. There's lots of action, which kept me turning pages - wolf attacks prompting wolf hunts, a half-mad werewolf... that sort of thing. Very entertaining. Similar titles (a little edgier and far less romantic) include: Sharp Teeth (Toby Barlow) and Liar (Justine Larbalestier).