I did it last year...as far as I know, the entire program started last year (2007), so this is just the second year it's going on. That said, it should have a good reputation...I mean, a huge biotechnology company (Amgen) partnered with some of the most prestigious universities in the US (Stanford, UC Berkeley, MIT, UCSF, etc.)...what's not to like?
Aside from weekly seminars, a weekend conference with all Amgen Scholars from all campuses at Lake Tahoe, and summer end poster and oral presentations, it's pretty much the same as what you'd expect from just working in a lab for the summer. I recommend it 👍...the best part is meeting your fellow Scholars from universities all around the US and Puerto Rico.