It's all about the Mac. Well, mostly.

Apple's (AAPL) Worldwide Developers Conference Monday, as expected, has concentrated on a refresh of the company's Mac lineup. For Apple, where Mac computers accounted for 20% of revenue in the 2011 fiscal year, this isn't just a question of adding whistles and bells -- although the company has done its best, from what I've seen, to justify the premium prices it charges for its computers versus PCs. 

So, for instance, the MacBook Pro is sleeker and lighter, but faster with instant on thanks to flash storage and an upgraded Intel Core i7 processor.

But the real goal of the refresh, I'd argue, is to bring the Mac experience more in line with the company’s iPhone and iPad. One of Apple's big selling points is the integration of its devices and this refresh seems intended to bring Apple’s computers closer to the iPhone and iPad. The refresh seems intended to walk a fine line between increased integration and so much change that it would alienate long-time Mac users. (Apple is a member of my Jubak Picks 12-18 month portfolio.)

To that end, the new operating system includes familiar apps from the iOS operating system on the iPad and iPhone such as messenger, reminder, and notes. The updated MacBook Pro will have the same "retina" display that looks so spectacular on the iPad. (And if you're looking for clues to the direction of Apple TV, you should note that the MacBook Pro comes with a HDMI slot to allow a user to connect the computer to a TV.)

Although the emphasis at the conference has been on the Mac line (except for a standup routine performed by Apple's Siri software that begins with a software developer joke: How many software engineers does it take to change a light bulb? None. Light bulbs are a hardware issue.), the company also announced a new version of its iPhone and iPad operating system (iOS 6) with important tweaks that are part of Apple's battle with Google (GOOG). 

For example, there's support for Baidu's (BIDU) search engine in China and closer integration with Facebook (FB) that allows Facebook users to post pictures and video to their Facebook accounts without launching a Facebook app and to post updates via Siri. Apple also announced that Siri is headed to the iPad.

The market hasn’t been impressed enough by this event to push Apple’s shares up against the general downward trend in the U.S. markets. Apple’s shares were down 0.91% as of 3:30 New York time today.

But I think Apple’s announcements Monday more than adequately performed two very important competitive tasks. First, the company added enough new features and buzz to the Mac line to keep it growing faster than the sluggish PC market. I know that’s not a tough hurdle to jump but Apple jumped it with a big margin in fiscal 2011 when Mac unit sales grew by 22%. Second, Apple’s timing keeps the pressure on Microsoft (MSFT) to deliver its new operating system on time this fall. If Microsoft slips, Windows devices are going to face a tough holiday selling season. (Microsoft owns and publishes Top Stocks, an MSN Money site.)

As of June 11, I'm keeping my $650 a share by December 2012 target for Apple’s shares.

At the time of this writing, Jim Jubak didn't own shares of any companies mentioned in this post in personal portfolios. The mutual fund he manages, Jubak Global Equity Fund (JUBAX), may or may not own positions in any stock mentioned. The fund did own shares of Apple as of the end of March. For a full list of the stocks in the fund as of the end of the most recent quarter, see the fund's portfolio here.