Personally, the reason I'm familiar with GB is because of Game Spot. That was the site that I visited in High School because the url
www.videogames.com redirected you to Gamespot.com (and still does to this day).
Back then Greg Kasavin was the EIC and the site had major credibility imo. The reviews were thorough and lengthy, which I really enjoyed reading.
Kasavin eventually moved on to game development around 06' and the reigns were passed on to Jeff Gerstmann to run the site.
The core staff for GS at this point were Jeff, Alex Navarro, Brad Shoemaker, Vinny and Ryan Davis.
Once Jeff was sacked for his review of Kane & Lynch, Alex took off for Harmonics and Ryan resigned within a few weeks.
You can see that Alex and Brad are not impressed to have to be involved in this super lame video that falsely explained the situation to the sites member's.
Within six months or so Giantbomb was a thing that Jeff and Ryan were promoting. By this point most forum posters who knew what was going on with Jeff and GS had bailed on the site. That's actually what prompted me to finally create an account here at GAF. Lurked for years, but Gerstmann-gate pushed me over the edge.
Anyway, the reason why people were drawn to GB--and the podcast in particular--is because these guys have years of experience in the industry. And while I can totally understand the non-game talk not being for everyone, it's the camaraderie between the core group of ex-Game Spot-ers that I'll always remember. Listening to the bombcast made you feel like a fly on the wall of a group of guys who were playing games that you only read about for months leading up to their release. That's something that many podcasts struggle with. It's also what made 1up Yours work and why 8-4 Play is what it is.
And let's not downplay the sites role in the industry. Look at their e3 coverage the last three years. They get industry people to come and talk about shit other sites 10x their size wish they could book. Quicklooks are now an industry norm. Not that they invented that concept, but they certainly helped bring it to the forefront for modern sites.