talent can't get "trapped" by a bubble: if a bubble is really a bubble then it will burst and the talent will become free. in fact if you feel there is a bubble then you should encourage it because over the long term the market will be flooded by talent which will be cheaper.
but something that everyone here has to think about: even if you don't think there is a bubble, the nature of tech is that it is cyclical in nature. this means that sooner or later there will be winners, and those looking for a job. although i dare say that those down cycles are in fact THE best times to start a new business or venture.
i would also say that at this point in time that most of the costs of most startups are talent. years ago this wasn't the case, and one of the things that screwed me over in the original dot.com bust was the fact that my real estate costs tripled in the same space at the high point of the bubble. i also wasted a ton of money on hardware and have bitter memories of owning expensive servers that were destined for eBay.
i should add that deeply respect 37signals, and i've found myself following their model -- but it's not the only model.