I hate it, for several reasons (some of it could be user error or local configuration, but still):
- For a long time, the status of other users it showed was completely off. Like showing people online when they weren't. Also, sending messages sometimes mysteriously failed.
- Cannot copy conversation as text (formatting is messed up). Cannot save it as text without removing smileys.
- Cannot paste text verbatim into conversation without making silly smileys everywhere.
- There is a (relatively small) limit on how much text you could paste in.
- Couldn't transfer certain files (like .js or .exe).
Many of these things make sense for things like unmoderated chat, but I need to work, and sometimes exchange larger amounts of text and binary data.