I got to discussing this with an online chat friend of mine this evening. My own take is that we will know that there is a sustained economic recovery in the USA when two things happen:

1. Tech employers start to lobby the Federal Government to increase the temporary visa caps
2. Employers start whining publicly about employees being "greedy", having "no loyalty", "ungrateful" etc. etc.

(1) will occur, because employers will find themselves under wage and salary increase pressure as employees, after an extended period of time where they were at the mercy of employers, will suddenly find themselves in demand once more.
(2) will be the response of employers who seem to think that they are owed loyalty by employees. In reality, most of them will have no right to expect loyalty, given the tendency of many employers to fire employees in the blink of an eye when they fear a loss of profitability. Every employee of a large employer also knows about the various tactics that employers have long adopted to circumvent inconvenient items of law such as the WARN Act, in order to reduce their costs or eliminate their responsibilities to laid-off workers.
When it comes to treating employees badly, the old saying "revenge is a dish best eaten cold" applies. Most employees will bide their time and act when it is convenient to them, sometimes many years later.