You're obviously very frustrated by how people see the service, but you can't blame them.
The GIMP incident made pretty big news, and for many people, the name "SourceForge" will stay equivalent to a malware-injecting host. Anyone who decided to keep the name should have anticipated that.
I'm not frustrated, but these threads show up on HN almost weekly now, with armchair quarterbacks who really are not current on the state of open source opining ill informed opinions. They even know we are new owners who immediately killed all the bad stuff, and still blame us. I cared about SourceForge, so I bought it and removed DevShare, and still get the blame. People know that we having nothing to do with the old owners, but recreational online outrage is fun, so they continue to blame us for saving it. Cognitive dissonance is en vogue right now. I guess if someone's lonely Sunday night is made better by shitting on the people who did everything in their power to save SourceForge, then go for it. I just think people's time can be used better.
Maybe change your name from source forge to something else.
You can rehabilitate the brand, but that will probably take a lot more money than just changing the name.
Edited to add:
On the front page I also see "Business VOIP" and "Cloud Storage" and "Internet speed test". Maybe you want to remove those links and focus on software development.
The GIMP incident made pretty big news, and for many people, the name "SourceForge" will stay equivalent to a malware-injecting host. Anyone who decided to keep the name should have anticipated that.