There are a lot of links to SourceForge on the web. As someone in the thread pointed out there are even spammers abusing it. People clicking on the links and making "sessions" doesn't constitute actual usage.
I doubt anyone in this thread uses SourceForge for hosting. I am not. And I wouldn't recommend it. If I asked my peers if they use it I'm certain that not a single person would say "Yes".
So yes, in my eyes it's dead.
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Oh I just opened the site and there are statistics on main page. 600 bug reports and 12k commits per week across all of the hosted projects is not really a big number. 10th most recently updated project was updated 1 month ago. Yes there are still some fairly large projects hosted (probably only for distribution) on SF and they receive considerable amount of downloads, but they're only there because they have been on SF for ages.
Without fresh blood, those projects are just the last breath of SourceForge.
Sincerely good luck. My point was that not only you have to fix the past, but also deliver better product. The market is quite saturated, people have choices, the end users are more tech savvy with higher standards, developers expect much more as well.