One star for the idea, finding romance in Vegas during a Star Trek convention. Everything else is horrible, though. Three out of four of the main characters don't have much knowledge or care about Star Trek, making the setting superfluous. All of the main characters are shallow, with single motivations that are hard to care about. Bianca is hot to trot, and is dealing with a failed marriage. Colby is scarred by her (literally!) from a past incident in junior high.
The book's length is very short, at 160ish pages, a lot of which are wasted with breezy, rambling dialogues between the two girls, and very little on the world of the con. Most of the relationship building isn't even caused by it. Except for the premise, this is bad, bland romantic fiction. Avoid.