I have to say, I'm always surprised that people complain about Betamax tape length. I had both 3 and 4 hour tapes and I expect that if Sony had continue development, I would have had LP and even EP modes. Whilst I do realize that very early on there was a length issue, this was not the case for most of the life of the product.
I think by then it was too late, VHS market momentum was too great - economy of scale and content support. Recording/play time was clearly a major difference between the standards in crucial momentum building phase. VHS had 2 hours, Betamax had only 1 hour.
I remember many of us having 120 minute VHS (later 240m) and a few having 60 minute Betamax (later 120m) at the time home video recording really took off (also, first Betamax half speed long play alternatives reduced the image quality advantage)
With respect to VHS being 'open', that wasn't the case either. I'm pretty certain that every VHS recorder sold included a license back to JVC.
Not according to Wikipedia. From http://en.wikipedia.org/wiki/VHS: "JVC believed that an open standard, with the format shared among competitors without licensing the technology, was better for the consumer. ". If this is wrong and there was a need for some form of licensing it was clearly very broadly and cheaply offered.