"The Hathaway Series" - Lisa Kleypas
I read these two out of order, but I had read them before... No matter that I was just too lazy to stop and look for 'Married by Morning' (it was on the kitchen table) so I just started 'Love in the Afternoon.' Which is the final book in the series, and a little bit anti-climatic. Beatrix is the most developed character when she finally gets her own love story, because she's featured in everyone else's stories, too. Her story is very much "Shop Around the Corner"/"You've Got Mail" inspired, and truly the letters were the best part of their story.
I remember being pretty disappointed in Leo and Marks' story the first time around, but that was due to some lofty expectations. This time it didn't bother so much.
Overall, Lisa Kleypas is so good at what she does, even her mediocre output is better than most romances published today. It's just that sometimes, what she puts out is amazing, so you want it all to be as good...