'Late Eclipses' Seanan McGuire: I've loved the Toby Daye novels from the beginning, and each successive volume just deepens and enriches the world and characters that McGuire has created. I held off as long as I could on this one, but still have a ridiculously long wait for the next.
'Heartless' Gail Carriger: Another series that I lovelovelove and wish had a new volume every month. Sorta Steampunk-y, sorta Urban Fantasy-ish, sorta Romance-like, there's just a lot to love about Ms. Carriger's fictional world. I also appreciate the fact that she's an author who's not above sharing a wink with the reader at the ridiculousness of some genre cliches.
'The Chase' Erin McCarthy: I don't get NASCAR, but I am totally hooked on McCarthy's contemporary romance series set in the world of stock car racing. They're not enough to make me want to spend my weekends watching cars go 'round a track, but plenty enough for me to put aside my admitted prejudices and devour each new volume in a single sitting.
'Beautful Dead: Summer' and 'Beautiful Dead: Phoenix' Eden Maguire: The last two volumes in a YA series that started off strong, but became a bit repetitive toward the end. However, I was invested enough in the characters that I couldn't not finish the series and see how it all ended. And, though the ending wasn't what I would have chosen, it worked and I wasn't too disappointed.