When it rains, it pours. Microsoft Office now appears to be under attack by four major – and I do mean major, maybe the four biggest names in the business along with Microsoft - competitors: Google, Apple, IBM and Yahoo.

Of course everyone knows about Google’s assault with Google Docs & Spreadsheets (now just Google Docs) which hit another new high last night with the release of the PowerPoint-competitor Presentations. There is also Apple which just released iWork ‘08, their office suite with a bunch of upgraded tools and an entirely new one, Numbers, to take on Excel. Now IBM is set to enter the mix with Lotus Symphony, a free OpenOffice-based desktop office suite. And even Yahoo is generating talk that they are entering the fold after their $350 million purchase of Zimbra, another open-source application suite.

Make no mistake, Microsoft’s position with Office is a completely dominant one, but with four competitors like this coming at them, Microsoft has to be doing more than just taking note. Perhaps that is why we saw a massive price-cut for students last week to buy the fully loaded office.

Office is one piece of software that an argument could definitely be made that Microsoft deserves such a lofty status; it’s been very solid for very many years. It does however have a weakness, and it’s a weakness shared by many things Microsoft does, the Internet. Google clearly sees this opening and is moving full-steam ahead, and it’s likely Yahoo sees the same thing (perhaps prompting what seems to be an overpay for Zimbra).

Apple and IBM appear to be going the more traditional office suite route for now, but IBM has a definitely plus in that it will be available for anyone to download for free online, and Apple’s suite looks very good to Mac users who still haven’t seen a Microsoft Office upgrade since 2004.

Trying times are ahead for Microsoft. But aren’t they always?