Snow Leopard

quite possible the only difference you'll see is more disk space left over, depending on your laptops spec, you might see quicker boot times but it wouldnt be that noticable

 

You should have no problems with the upgrade

However, don't expect any real noticeable or exciting changes in the interface or performance

 

I have done so, and besides Safari being a pain in the ass, it works okay, but sometimes I wished I stayed with Leopard, or better, Tiger, as those were more stable

The thread title snail strikes again:

A more descriptive and precise thread title will help cater to the right audience and get you more responses.

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Have you also taken a look at MRoogle, since that question may have been asked several times?

 

+1

SL has been rock solid for me. Only negative point for me is they're rearranged the way Spotlight results are shown, they're not grouped by type any more. Grrr.

Also, you might have to upgrade some software which might cost $$$$.

IMHO, not worth the upgrade until Apple stops supporting Leopard.