(Updated 3:50 p.m. PT with details about the "400.")

VMware says it ended 2014 with 400 NSX customers for the NSX network virtualization platform, up from 250 in September and 150 in June.

VMware made the announcement today in conjunction with its fourth-quarter earnings. The earnings release didn't attach a dollar figure to the NSX business, though. We haven't heard a dollar figure for NSX since July, when VMware said the platform — which had been shipping for only one quarter — had reached a $100 million run rate.

VMware also didn't include the adjective "paying" this time. Its third-quarter report noted more than 250 paying customers for NSX; it's possible that this quarter's total of 400 includes some non-paying trials.

(Update: A VMware spokesperson notes these are, indeed, 400 paying NSX customers. During today's earnings call, VMware also revealed that NSX is on a $200 million annual run rate for bookings and that the platform closed its first $10 million deal, with an investment bank. Nine of VMware's top 10 deals in the fourth quarter involved NSX.)

So goes the one-upsmanship as VMware and Cisco each try to prove that their platforms for software-defined networking (SDN) are gaining traction. The companies' metrics aren't directly comparable, partly because Cisco appears to count every buyer of Nexus 9000 switches as an Application-Centric Infrastructure (ACI) customer. But in a press conference earlier this month, Cisco Senior Vice President Rob Soderbury did say that the company is "pushing 100 deployments" for the Application Policy Infrastructure Controller (APIC), the software engine that brings out the "SDN" in the 9000s.

VMware tends to de-emphasize the rivalry, noting that its NSX and Cisco's ACI don't perform the same specific functions and could even be used together. But both platforms are being pitched to customers as vehicles for SDN or a similar transformation. They're in competition for mindshare if not budget, according to analysts and some customers.

The rivalry got an extra wrinkle over the holidays, as VMware's networking division added some notable engineering talent out of Cisco.

For its fourth quarter, which ended December 31, VMware reported revenues of $1.7 billion and net income of $326 million, or 75 cents per diluted share. Analysts were expecting revenues of $1.69 billion, according to Thomson Reuters.

Non-GAAP net income of $1.08 per share beat the analysts' consensus estimate by a penny.

For its fourth quarter a year ago, VMware reported revenues of $1.48 billion and net income of $335,000, or 77 cents per diluted share.