Right now in front of me, Sparks! 1.7.16 is running on Windows, Linux and Mac. We've made a number of changes to improve and make more reliable the Linux and Mac versions, but there's a still a fair distance to go before we're totally happy. This is what's in the works:

• We want to release the Linux version as a "turnkey"; that is, you install and run. No more dealing with installing various subpackages — there's just too many incompatible versions of wxPython out there.
• We're compiling wxMozilla for Linux right now.
• There's almost an wxPython-embedable version of Safari for the Mac. Almost. Stay tuned.
• Until the browsers are working on the Mac and on Linux, we're not going to stress the blog reading cabilities of Sparks!