Where Fantasy meets Romance ...
I grew up reading Fantasy and SF, didn't know it was a genre but loved it all the same. I read Georgette Heyer's regency stories, never realising they were 'Romance'. They were just great stories, which happened to have a love story as the central theme.
I like a book which has a love story running through it. Love is a great motivator, whether it's a mother's love for their child, a king's love for his people, or the love you have for someone special.
The characters in my fantasy trilogy, King Rolen's Kin, are motivated by love, love for their family, love for that special person, some even suffer unrequited love. They are also motivated by ambition, the need to see justice done and, sometimes, the simple need to survive.
That's the difference between a Romance book and a Fantasy with a love story. Romantic love is the prime motivation in a Romance, while it is one of many/several motivations in a Fantasy.
Having said that, the line between some Dark Urban Fantasies (as the Romance field defines them) and Dark Urban Fantasies (as the Speculative Fiction field defines them) is getting finer and finer. Take Trent Jamieson's 'Death Most Definite' and Tansy Rayner Robert's 'Power and Majesty', both are published by speculative fiction publishers, Orbit and Voyager respectively.
Trent's trilogy is set in Brisbane were Death is a business, Tansy's trilogy is set in an invented city which is threatened by supernatural means. In the first books of both these series love is a strong motivation. In Trent's book the main character, Steve, falls in love with a dead girl (it's not icky, he can see dead people and she's there to help him). In Tansy's book the main character, Velody, is swept into the supernatural world filled with very sexy, rather menacing males. There's bucket loads of passion and sensuality. Both books have drama and action, both books have sex and love, and both books end with the promise of more to come (no Happily Ever After).
Now compare that to your Romance Dark Urban Fantasy -- the protagonist, a feisty female, is swept into a supernatural world, where sensual, menacing characters interact with them, and team up while they fight off evil. Plus there's no HEA because the main character goes in to further adventures in a series.
So there you have it. A Romance or a fantasy with a love story, the line is getting ever thinner!
The King Rolen's Kin Trilogy came out in July, August and September of this year. I had a new fantasy trilogy - The Outcast Chronicles due out in 2012.
See Rowena's blog here.
Her web page here.