Dionysius, God of Wine and Leaf, writes with a link to a New York Times story on a source of pollution that doesn't leave contrails: "The world's data centers are projected to surpass the airline industry as a greenhouse gas polluter by 2020, according to a new study by McKinsey & Co. ... [C]omputer servers are used at only 6 percent of their capacity on average, while data center facilities as a whole are used at 56 percent of peak performance." Data centers, though, might have more options for going green than airlines do, given present technology.

mksmac writes "According to the KOMO TV Website, Microsoft has withdrawn its bid for Yahoo after presenting them with an increased offer that was subsequently declined by Yahoo. Frankly, this seems like a smarter decision on Microsoft's part, but I'd like to hear how other people feel about the deal. Should Microsoft have walked away, pressured Yahoo via a hostile takeover or sweetened the pot until Yahoo gave in?" For those who prefer it, the NYT also has coverage, and the story is also at news.com, among many others. I like the Beeb's version as well. And for the Microsoft-centric explanation of why the courtship is over, see Steve Balmer's letter to Jerry Yang.

andrewmin writes with an enthusiastic pitch for Google's closed-beta call-aggregation service called GrandCentral, for which we non-beta-testers can at least reserve a number. Specifically, he's using GrandCentral in combination with Gizmo5 to make free VoiP calls. Excerpted: "Most of the time, I'm at my computer. Or near it. And if I had an internet device like a Nokia N810 or an iPod Touch, I'd have it with me 24/7. And since most of the time I'm at a place where there's a WiFi network, it makes sense for me to use VoIP rather than a regular phone line. ... I'm talking about making and receiving calls that are completely free (that is, $0.00/minute) forever (that is, no 30-day demo) for as much as you want (that is, no 30-day trial or five hour/week limit)."

Roland Piquepaille writes "Networks are used to represent the structure of complex systems, including the Internet or social networks, but often these descriptions are biased or incomplete. Now, researchers at the Santa Fe Institute (SFI) have shown that it's possible to extract automatically the hierarchical structure of networks. The researchers say their results 'suggest that hierarchy is a central organizing principle of complex networks, capable of offering insight into many network phenomena.' They also think that their algorithms can be applied to almost every kind of networks, from biochemical networks (protein interaction networks, metabolic networks or genetic regulatory networks) to communities in social networks. But read more for additional references and some pictures about hierarchical networks and their applications."

IBM Developerworks' latest was submitted to us by an anonymous reader who writes "Using Firebug and YSlow, you can thoroughly analyze your Web applications to make educated changes to improve performance. This article reviews the latest tools and techniques for managing the performance of Ajax applications along the life cycle of your application, from inception through production."