From the homepage:
We are saddened to announce that there will be no future versions of Fire. There are several reasons for this end, but the most notable is the loss of developers. Fire's development had dwindled to few developers who do not wish to continue the project alone. In addition, another major contributing factor is the fact that all but one of Fire's IM libraries is no longer in active development.

The good news is that two of Fire's developers have joined the Adium team and have written a transition path. Adium 1.0, upon first launch, will import your Fire accounts, away messages, groups, buddies, and logs into Adium. For future updates and IM needs, we suggest that you look at Adium.

I use Fire even though it is completely crashy. I like the voiceover/speech function, and I think Adium is completely ugly compared to Fire.

Note to the administrator: I've got an icon for this app ready to upload. E-mail me at marnen@marnen.org and let me know where to send it.

Fire is an excellent multi-protocol IM client. I've tried Proteus and Adium, and I don't like either one nearly as much as Fire.

I was a Adium user until this latest version, it crashes all the time on my new macbook pro. Fire is a very soild and stable app. Very much worth your time.

sirmarcos = "how on earth can Adium have so many more users than Fire? Fire is vastly less confusing..."

answer = because Adium is not confusing at all, does the same things, is more customisable, and looks better.

how on earth can Adium have so many more users than Fire? Fire is vastly less confusing... and Adium can't even mute individual chat window sounds like Fire can.