CNet has an interesting profile of MySQL, JBoss, and Zimbra, exploring what an open source company is actually worth. "Given how slowly revenue accumulates in an open-source company--assuming it is recognizing subscriptions over 12 months--bookings is probably the valuation metric being used or at least strongly considered. It surely is the metric by which the start-up wishes to be measured. So while Savio suggests we open-source entrepreneurs may be "sleeping with dollar signs in (our) eyes," there's clearly a lot of work to do before most open-source companies are worth selling. It's not worth selling out for $100 million. Not for the venture-backed companies, anyway."