For me, it depends where the bio is being written and which character it is.
Because of that annoying word limit, my in-game bios are usually just really messy, profile style things that leave out most of the actually important stuff.. Or I don't bother trying to write anything there at all x'D
When I have an unlimited amount of space to type (The forum, for instance), motivation, and time, I go completely overboard with EVERYTHING. This is something I only just started doing recently (AKA 3 days ago), but it will typically contain...
- Basic info such as name, age, breed, etc
- Relationship stats
- About 657456 (Okay, so maybe that's an exaggeration) paragraphs explaining his/her personality + Random rambling
- The theme song, also explaining how it relates to the character
- Information about any powers the character has, if any
- Quotes
- etc
However, the bio may range in size, depending on the character. For instance, Boogie is my fursona, so his is somewhat shorter because I don't roleplay with him. And Saischa, Summit, and Scragues' (Well, not the one of him I posted here. That was a huge WIP) bios are huge because I write about the three of them and they're all extremely complex when it comes to their powers and stats.
My single character bios (such as on FH chars) are generally just the norm e.g
Gender
Age
Breed
etc...
Then theres my full on character RP bios. Which tend to last a page, usually written in first person. Then they add the details to their own story, much like a diary or an interview. I try to make them as personal and descriptive as I can
writers block rules my life though, so it usually ends up a babble of nothing
My bios are always pretty straightforward, with just the necessary information other people might want to know. I kind of envy the people who can manage to write an amazing backstory and still have room to place in all the needed information about their character.
It's kind of annoying when people use a different game window size and your bio layout looks goofy, so I never use too many ;/:/./,/>/</*/^/| decoration symbols.