Salaries may increase but more likely it will become like wall street for the most valued employees--that is, a bonus & stock options culture. So, for example, your base is 90k with 30k in options that vest in 3 years and a 15k year end bonus. So if you're thinking about making the jump to MegaCorp Inc. they're going to need to offer you a significantly better deal to cover your lost earnings.

Doesn't this happen already? Moreover, I don't think it will ever get as unbalanced as wallstreet compensation was at the height of the financial boom simply because we aren't as "close to the money" as traders are. E.g. A trader has a P&L so it's very easy to calculate how much value he brings to the firm. For an engineers working in industries other than finance the calculation isn't as straightforward and requires more art (read: politics) than simple calculations.

Note that this could in part be an attempt to circumvent the unenforceability of non-competes in California.

I keep banging on this drum, but it bears repeating: Silicon Valley/the Bay area is unique in the world, and compared to other would be competitors, in the US at least, is unique when it comes to public policy on non-competes.