By now, I'm sure you've read IDC's latest Worldwide Quarterly Server Virtualization Tracker report.  It talked about worldwide virtualization license shipments in the second quarter of 2008, worldwide virtualization software revenue grew 15% year over year in 2Q08, Hewlett-Packard held onto its number 1 spot for worldwide new server shipments virtualized with 34% market share and 52% year-over-year growth, VMware grew its x86 server virtualization software business 27% year over year and maintained the number 1 position in the market with 78% revenue share in 2Q08, and the interesting piece of information that is being called into question by some is that in its first quarter of general availability Microsoft Hyper-V delivered a strong showing, and when combined with Virtual Server 2005, Microsoft’s market share is 23% of new shipments.

Are the numbers all accurate?  Are they ever?  I've been at this game of virtualization for 10 years now, and one thing seems to hold true - whenever a report comes out, numbers are always skewed in some way.  Not necessarily intentionally, but reports come out with numbers that differ from other reports.  Sometimes they are close, sometimes they aren't.  And unless you look at all of the reports at the same point in time, many don't question it.  Are the numbers in this IDC report 100% accurate?  I'll be the first to admit, I have no idea.  I don't have access to the raw data.  In fact, when I ask companies like those in this report for numbers, they usually give me the same answer, "We don't supply these types of numbers outside of the company."  Great!  

So let's hear from the other side of the equation.  I found the following response to IDC's virtualization report at Mike DiPetrillo's blog site.  Yes, he is a VMware employee and states so on his blog.  Rather than just read one piece of information and then formulate your entire life's opinion on it, you might want to read around and question things.  And Mike is always one to question things.  ;)  And this report is no different.  Here is his recap:   

This Was a Sponsored Report

 

As with most analyst reports this one was sponsored. IDC won't give up the name of who actually sponsored it but I can tell you it wasn't VMware and the ones that did sponsor it are a competitor in Redmond. That's just fine that people sponsor reports and I would have no issue with it as long as the information was accurate. When the firm putting out the report just publishes inaccurate or incomplete date then they look as foolish as Forrester did when they wrote about Open Source adoption. I'm actually surprised that Matt Asay didn't pick up on the inaccuracies in this IDC report. I guess we have to give him some time since usually he's spot on.

Recap

 

Here's the main points you need to know about this report from IDC:

1) This was a small sampling using just the OEM's numbers.
2) How do you count unit shipments for free products not delivered by the OEMs?
3) Microsoft only went up 5% from the previous measure.
4) VMware also went up 2% from the previous measure.
5) Hyper-V was only shipping for 2 business days in Q2 2008. There was no Hyper-V impact to these marketshare numbers.
6) VMware still commands a huge lead in actual product use.
7) There are real factual errors throughout the report.
8) This was a sponsored report with no input on revenue, shipment details, or feedback from VMware.