[simonh]

While market cap may not be the actual realisable value of the company, that doesn't mean it's irrelevant. It's perfectly relevant when comparing the relative value of different companies, especially when they are in similar sectors. That's especially true when companies have very different numbers of issued shares.

Even then, market cap does actually correlate directly to realisable value in acquisitions. They rarely trade for exactly the market cap, but it's definitely a useful benchmark against which to compare the company's relative value to the acquirer and it's current owners.