Well looking at Hollywood the mega-producers tend to gravitate to big films that are focused on box office rather than creating a great film. The producer has more insecurity than a writer/director so creativity is substituted for short cuts like a well known license or a big star in a safe film. The result is a film like Transformers -- cool eye candy, makes real money yet it's an average film.

I prefer a VC model where Weinstein brothers find a Tarantino and make a film that not only makes money but can be watched with admiration for years to come. This isn't to say that Hollywood producers in days of old weren't talented, but these days you get bland product.

The same thing will happen with tech. A VC as producer may be good at identifying a unique niche that needs a product (say medical billing software) but you won't get a gem like a Flickr or Facebook that way. And that's not to say that the producer model is wrong, but it's not as much fun.