"Dragon Effect", because this game borrows some elements (voiced protagonist, dialogue wheel, greater focus on action than tactics) from Mass Effect.
The female Hawke is called Lady Hawke by some of the fanbase. "Mike" is a favorite name for Male Hawke, for some reason...
Also, a Hawke with a diplomatic/nice personality is sometimes called "Paragon!Hawke", while a Hawke with an aggressive/serious personality is called "Renegade!Hawke." A Hawke that usually takes the middle dialogue options and develops a sarcastic personality is often called Silly!Hawke.
As an additional note, the Japanese version of Dragon Age II is the first game of the Dragon Age saga with Japanese voice acting, since the prequel only had the original English voices with Japanese subtitles and text translations for everything else.note In fact this is the first BioWare game with any Japanese voice acting at all, since their other games weren't released there or without Japanese voice acting. It had something to do with the fact this game will be released in Japan by Spike and not by EA's Japanese branch unlike their other games.
Isabela has a different voice actress, since her voice was exactly like the character her previous voice actress played, Queen Anora.
Merrill has a different voice actor in the second game since the Dalish now have Welsh and Irish accents.
Anders too. Previously voiced by Greg Ellis, who also voiced Cullen (in both games), he is now voiced by Adam Howden (heard as Silas Corthwaite in Leliana's Song) because unspecified "shenanigans" made it impossible to hire Ellis for such a large role.
Cassandra has a different voice actress in the anime, Dawn of the Seeker, than in the game.
Dragon Age 2 was originally going to be a Gaiden Game called "Dragon Age: Exodus" with the plot for what would later become Dragon Age III being planned for Dragon Age II. Among other differences, Hawke was originally intended to be an NPC named Ulrich Von Hawke who was a werewolf with a tendency to Lick the blade: this is the origin of the out of place blood splatter on the default character appearance.
Anders wasn't the only candidate for the "renegade mage" role. David Gaider has said that Velanna was also considered in early development to potentially join Hawke's companions and serve as the new host for Justice.
The boss fight against Orsino was originally going to be exclusive to the Templar endgame. However, it was added to the mage endgame for the sake of another boss fight.
Anders' cat Ser-Pounce-A-Lot was going to still be around, walking around in Anders' clinic. However, he was cut since it would require making a new character model.
The Exiled Prince DLC was originally going to have Nathaniel Howe play a major role. While Nathaniel can still appear in the main game, he was cut from the DLC due to the possibility of his death in Awakening.
Much like how Origins has Awakening, Dragon Age II was going to have an expansion pack called Exalted March but was cancelled due to other projects. Some of the story elements are (apparently) being kept for Dragon Age III instead.
There was supposed to be a third post-release story DLC, but it was at first lumped with Exalted March, and then canceled altogether along with it. The basic storyline, however, has been worked into DAI.
Those who lamented the fact that Varric was not a romance option could be either cheered or further disappointed by the statement that an extra scene was cut from the very end of the game. According to Word of God, there was to have been a scene after Cassandra releases Varric, in which he reunites with Hawke and reassures her/him that while he did tell the Seeker the whole story, "I didn't tell her anything about us."