Without changing physically, Harley's character varies depending on the writer. Many people were turned off by the animated version and never gave her a chance afterwords. What they have missed out on is an in-depth character with more to her than "Mistah J" and "puddin."
 
1. Animated TV Show Harley - "Mistah J!" "Puddin'!" Here we have the original intended to purely be Joker's sidekick who brings out a side of the Joker we had never seen prior to her existence. She's fun-loving, goofy and crazy and gained popularity because that is a good combination for a cartoon character.
 
2. Kesel's Harley - Jump ahead 2 years to her very own 2000 solo series! Karl Kesel stayed true to the core character and wrote a ridiculously weird 25 comics about Harley 
going solo with her own group of henchmen. Well, at the time it was relatively successful , but the character was no longer dependent on the Joker. She relied on causing mild scenes in Gotham and relationships/socializing with other people.
 
3. AJ Lieberman's Harley - When Kesel was done, Lieberman wrote #26-38 of her solo series. Many people HATED or ignored these issues because she was written similarly to Catwoman or a sadistic Batgirl. The jokes are few and far between and she is ruthless and murderous and relies on no one. The soft side is there, but the comic relief is mostly gone and is the polar opposite of Harley #1 and 2. She is constantly stealing while being conflicted about love and doing the right thing morally.
 
4. Arkham Asylum/Suicide Squad Harley - Not sure on this yet, but the pictures lead me to believe she had drastically changed again. For the better or worse, who knows? She hasn't shown much personality yet, but I'm seeing little similarities between this one and any of the previous three.
 
If I had to chose I would take #3. How about you?

I'm half way into the run of Gotham City Sirens and got to the issues about Catwoman's sister Maggie Kyle aka Sister Zero. I checked out her back story a bit and it was rather uninteresting and underdeveloped. She was more or less an afterthought. However, GCS has turned this somewhat forgotten character into an in-depth multi-dimensional character. I would love to read a mini series about her tracking down Black Mask or fighting some more demons of her past and revealing more origins. The Sister Zero character is way too cool to be forgotten. Anyone agree? Disagree?

When I just began collecting comics I realized Deadpool was my favorite because he "looked cool" and had a funny, kid-friendly (and violent) personality. I still have his original 4-comic series and first appearance in New Mutants and cherish those comics to this day. After a while, comics stopped being interesting to me as I could not afford to buy them regularly and the hobby passed me by around 2001.

Fast forward to 2011 as I am not an adult and recently got back into reading and collecting comics. Naturally, one of the first I look at is my old favorite: Deadpool only to find that he appears in SEVEN current series that revolve around him and also has many one-shots and cameos and many of the main Marvel series. I would have been thrilled back in 1995, but this Deadpool is watered down and just plain unlikable. Have I just grown up, or is the industry playing Deadpool for all he's worth while they can? You be the judge, but I sure know how I feel.

 Batman: the Dark Knight 1-6 (2011)
batman 608-619
batman: the killing joke
harley quinn 12-38
megacity 909 1-8