What I find interesting is, outside of romance, it appears that novels told from two povs are pretty rare. Single viewpoint novels abound, especially in first person, and novels with more than two pov characters also abound (most often in limited third, but sometimes in first, or switching between first and third for different characters). But googling "novels with two pov characters" etc. gives me tons of links for novels with
multiple viewpoint characters.
I don't think this should be a discouragement. A writer should pick the number of viewpoints that best serves the story.
The thing you should be crystal clear on prior to constructing a query is whether or not your novel truly has two
protagonists, or whether you have two
viewpoint characters, one of whom is the plot-driving protagonist. Even in romance, it's common for one character (usually the FMC in M/F romances) to really be "the lead," as in their life situation or problems get the plot bunnies hopping. The other character has goals and issues too, and they will affect the plot in many ways, but they will be nudged along by the other. In true dual protagonist stories, the relationship between the two characters drives the plot in a very symmetrical way, with neither one doing most of the leading nor following (or acting and reacting). Or the two characters may have entirely separate or parallel stories going on, but they are interwoven, or will eventually merge, in some way.
Here's a list of books that have two or more pov characters with distinctive voices.
http://www.penguinteen.com/10-books...prove-two-or-more-voices-are-better-than-one/