Is it worth customizing layout for firefox 2 only?

[derfelix]

Hello everybody..
I am working on a layout that is mainly tablefree...
Some parts use special visual effects... using css inline-block..
Works fine in all browsers (tested from IE5.5 up, opera 7, safari 3, chrome, and firefox 3)
BUT layout is completely broken in firefox 2, because it doesnt recognize inline-block.

I use -moz-inline-box instead for firefox 2, but it doesnt give the expected result..

MY question: are there still lots of firefox 2 users out there? is it worth it to change a layout completely just for firefox 2 users only?
OR can I assume that most firefox users have upgraded to firefox 3. ???? ( i read that over 3 million downloaded FF3 the first day it came out...)


Thanx for your advice...

Luc

PS: if someone wants to know why i need the inline-block, its for a gallery, i do NOT want it floated left.. but centered.. dynamically .. having the a variable amount of thumbnails per line, depending on the browser window size...
Centered because if i float it left, i will have a 2x as big margin left, when i resize the browser window...
As an example sites that use this technique.. are deviantart.com...
But i cant use the code they are using because i want some extra block elements inside the imagebit... and (difference to them) I do NOT have the size of the image in pixels .. so i can only vertically center the image in ie with an inline block..
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