Steve Jobs maybe skipping the opening keynote at Macworld Expo on Tuesday, but there are still plenty of reasons to be optimistic about this year's event.

Here are just seven...

1. Brand new 17-inch MacBook Pro

When Apply re-engineered its laptop line last October, it left out its biggest and best - the 17-inch MacBook Pro, which received a mild makeover instead. This desktop replacement is expected to finally get an update this week, with a new unibody enclosure, Nvidia chipset and possibly even a battery-saving OLED display. That maybe just as well - current rumours suggest that the 17-inch MacBook Pro's battery will be non-removable like the one in the MacBook Air. It's hard to see how this makes sense, especially when its 15-inch sibling has a removable cell. However Apple Insider claims the fixed-in MacBook Pro battery will have a 50 per cent longer life between recharges that the one in the current model.

2. Brand new Mac mini

It's been so long since Apple's headless Mac got an update that it's long been EOL'd by many fans. However a brand new version looks set to appear during Apple's Macworld 2009 keynote tomorrow. The new Mac mini will sport an Nvidia chipset, five USB 2.0 ports and both mini DVI and mini DisplayPort connectors, according to Apple Insider. However, Apple is also likely to kill off FireWire 400 with this update, the Mac mini opting for a faster FireWire 800 connection instead.

3. Brand new iMac

It's been 14 months since Apple last rolled out a brand new iMac - and rumours suggest Macworld Expo could be the place to finally reveal its replacement. Again Nvidia chipsets are expected to loom large, as are Intel i7 quad-core processors, and possibly even OLED displays. Ars Technica suggests that the iMac's enclosure will go largely unchanged, but we could see a 28-inch model make its Macworld 2009 debut.

4. Mac Home Server

Some rumour sites have suggested that Apple may launch its own take on Windows Home Server. The Mac Home Server will take essentially be a beefed-up version of the Time Capsule Wi-Fi / backup box we have now, but will enable you to access your files remotely using MobileMe.

5. The iPhone nano / iPhone pro

Speculation surrounding new version of the iPhone has reached fever pitch in recent weeks, suggesting two possible avenues for expansion. The first is the iPhone nano - a small, scaled-down version of the current iPhone, which aims to make Apple's smartphone affordable for everyone. At the other end is the iPhone pro - a beefed-up version of the current iPhone, complete with a physical QWERTY keyboard, more memory and wider selection of business-oriented apps. Both ideas seem plausible, even if they're more fanboy fantasy than anything else. A 32GB version of the current iPhone could also be on the cards.

6. Snow Leopard, iLife and apps for the cloud

Phil Schiller may not have Steve Jobs' charisma, but this section of his keynote is bound to excite hardcore Mac fans. Apple is expected to reveal a lot more detail about Snow Leopard - the next version of the Mac, iPhone and iPod OS. You should also expect a new version of iLife - Apple's creativity suite, which includes GarageBand, iMovie, iPhoto, iWeb and more. Some rumour sites are suggesting too that Apple may turn its productivity suite iWork (which includes Keynote, Numbers and Pages) into web-based applications in order to compete with Google Apps and Microsoft Office Live Workspace. There are rumours this could happen with iMovie, too - although the prospect of uploading and editing DV or HD video footage online isn't one we particularly relish.

7. One More Thing

Apple has been typically dismissive of the Netbook phenomenon surrounding the Asus Eee, but rumours suggest it has a similar device of its own up its sleeve. Certainly a mystery device bigger than an iPhone, but smaller than a MacBook was tagged on the internet pre-Christmas. This could be the oft-rumoured Apple Tablet - a multi-touch device with a 7-inch or 9-inch screen that Apple has been reportedly working on for months. TechCrunch suggest that the Apple Tablet may not appear until autumn 2009, but there's no reason why it might not hit earlier - the presence of mysteriously covered banners in the Macworld Expo shows halls suggest something cool is on the cards.