What about the current situation is bubble like? The wages of engineers? Certainly not. The fact that companies are being purchased? That has been the silicon valley model for decades; avoid the R&D costs for your large company by doing hardly any R&D and instead purchase whatever tech you think you need from the near-infinite number of startups clamoring for a payoff.
Are housing prices in a bubble? If so, that isn't exactly tech, and I don't think anyone could point to anything like this except maybe in San Francisco and Austin. Even so, the reason prices in those areas are high is due more to foreign investment than it is to geeks.
If any economic categorizations other than "normal" are appropriate than they are "depression" or "recession" rather than "bubble". I haven't perceived any significant change since 2008. Companies remain stingy. Unwilling to train. Unwilling to pay for the talent they need. Commonly using outsourced labor (which blows up in their face almost without fail). We work in an industry with extensive collusion among the major employers not to compete for employees (yes, this is still happening) and where no one is willing to form a union.
By what metric are we experiencing a bubble? Do we mean a negative bubble?