[color="900,0,0"]Visual Novel =/= Dating Sim[/color], come on are you guys even trying? While the two may overlap (a VN might have dating sim elements or vice versa) they're entirely different things. Let's get this straight:
Visual novels are distinguished from other game types by their extremely minimal gameplay. Typically the majority of player interaction is limited to clicking to keep the text, graphics and sound moving (most recent games offer 'play' or 'fast-forward' toggles that make even this unnecessary).
Most visual novels have multiple storylines and many endings; the gameplay mechanic in these cases typically consists of intermittent multiple-choice decision points, where the player selects a direction in which to take the game. This style of gameplay has been compared to the Choose Your Own Adventure books. Most, however, strive for a higher level of plot and character depth than the aforementioned series of interactive children's books. These can be more closely compared to story-driven interactive fiction. While the plots and storytelling of mainstream video games is often criticized, many fans of visual novels hold them up as exceptions and identify this as a strong point of the genre.
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Pic: Remember11
In a typical dating sim, the player controls a male avatar surrounded by female characters. The gameplay involves conversing with a selection of girls, attempting to increase their internal "love meter" through correct choices of dialogue. The game lasts for a fixed period of game time, such as one month or three years. When the game ends, the player either loses the game if he failed to properly win over any of the girls, or "finishes" one of the girls, often by having sex with her, marrying her, and/or achieving eternal love. This gives the games more replay value, since the player can focus on a different girl each time, trying to get a different ending.
Dating sims such as Tokimeki Memorial often revolve almost entirely around relationship-building, usually featuring complex character interactions and branching dialogue trees, and often presenting the player's possible responses word-for-word as the player character would say them. Dating sims such as Tokimeki Memorial, and some relationship-based role-playing games such as Shin Megami Tensei: Persona, often give choices that have a different number of associated "mood points" which influence a player character's relationship and future conversations with a non-player character. These games often feature a day-night cycle with a time scheduling system that provides context and relevance to character interactions, allowing players to choose when and if to interact with certain characters, which in turn influences their responses during later conversations.http://oi44.tinypic.com/mx0xs7.jpg
Pic: Love Plus
The difference is that a visual novel is mostly a linear story with choice points that influence the outcome and dating sims are statistic based dating games that repeat the same formula over and over again. Going by these definitions, something like Dragon Age or Mass Effect has more dating sim elements than Katawa Shoujo has.