Shares are tumbling this morning. The stock was down more than 6 percent in early trading, erasing more than $8 billion in market value. Look beyond Wall Street’s bottom-line disappointment though, and executives revealed some interesting details Thursday.

Google’s sales numbers were actually a bit stronger than analysts expected on average – the company just hired more people than it had planned. That, and earnings came in at $3.56 per share on $2.72 billion in revenue, short of the average estimate of $3.59 on $2.67 billion. (Google came far short of the high estimate, $3.93. Hate to be that analyst this morning.)

So. Considering those facts, Wall Street is now punishing Google for overspending on talent. The company added 1,548 workers in the quarter, up from 1,152 at the same time a year earlier. Google ended June with 13,786 employees, up 76 percent during the year.

That’s the bad news, which most investors are probably quite familiar with by now. Here are five points some might have overlooked in their rush to poke the sell button:

1. iGoogle. CEO Eric Schmidt revealed that Google’s homepage product has gone “from almost no users when it is introduced to many, many millions of users very, very quickly.”

2. Wireless. Google is committed to pursuing a future of open wireless networks for phones and other devices, where people can freely and simply, in Eric Schmidt’s words, “get a device, plug that device into a wireless network and be able to use the full capability of the Internet.” Why? Those people will “become very significant Google advertising users.”

3. Global. International sales now make up nearly half of Google’s revenue – 48 percent – and that has been growing faster than expected. Part of Google’s increase in costs was adding sales and engineering employees overseas. Those folks will help the company compete with Yahoo (YHOO) and Microsoft (MSFT).

4. Payroll. Google finance chief Greg Reyes said a different way of calculating employee bonuses was “one of the larger drivers of payroll expense.” He also said the resulting ding to Google’s earnings should be a “one-time inflection.”

5. Apps. More corporate customers appear to be moving software functions to Google’s hosted apps; Larry Page noted that one customer moving to Gmail “migrated 30,000 users with 3 million emails in just 24 hours.”