PC Worldis Biggest Tech Disappointments list for 2007 is out, and Microsoftis Windows Vista operating system ranked at the top of the list. Microsoft wasnit alone on the list, however, because Appleis iPhone and Mac OS X 10.5 operating system made the cut as well.

"Five years in the making and this is the best Microsoft could do?" PC World said. "No wonder so many users are clinging to XP like shipwrecked sailors to a life raft, while others who made the upgrade are switching back."

Years over due, and missing promised key components, Windows Vista seems to be disappointing customers as much for what is does have as for what it doesnit. Many Vista users have been complaining about extensive driver incompatibilities, hefty hardware requirements, and constant "security warnings."

PC World had a bone to pick with Apple, too. Mac OS X 10.5, or Leopard, came in at number eight on the list because of wireless networking issues, administrator account problems, and a file transfer bug.

"Maybe we just got spoiled by the iPod and iPhone, but the glow came off Steve Jobis halo after this feline fleabag debuted. Within days of its release last October, Mac users reported dozens of problems with the new OS, some more serious than others," PC World said.

While the iPhone was praised at the expense of Leopard at one point on the list, the combination iPod and smart phone earned itis own slot at number five. PC World bagged the iPhone for its touchscreen keyboard, lack of Flash support, reliance on AT&T, and the surprise US$200 price drop only weeks after the device launched.

"Yes, we know. Sliced bread only wishes it were as great as the iPhone. And aside from minor flaws like a tiny touch keyboard and lack of Flash support, the phone itself is pretty terrific. But AT&Tis;broadband service? Definitely second-rate."

The list also gave the iPhone a ding for what it considered an intentional move on Appleis part to permanently disable units that had been hacked for use on other cell carrier networks.