You can't search and replace, password-protect files, apply hyperlinks or in-presentation links, or control presentations on another device -- all things Keynote can do. You can't apply transition and build effects to individual items as Keynote can -- just to entire slides -- though any such item transitions are at least retained when opened in PowerPoint for iPad. You can see comments made on the desktop version of PowerPoint, but not add your own.
The notes view obscures your slide view (a flaw shared by Keynote). I often couldn't type notes in existing presentations -- the onscreen keyboard would not display -- nor could I paste text into the notes in those cases. PowerPoint also crashed several times when saving new documents.
PowerPoint for iPad is more than a viewer but less than a creator. It's fine for basic editing and simple presentations. But road warriors can do so much more in Keynote.
Office for iPad is free, but at a cost
Office for iPad is free but allows editing only if you pay for an Office 365 subscription ($10 per month for a family, and $12 per user per month for a business subscription that covers just the Office software, not Exchange and related communications services). Otherwise, you can only preview files, which is useless because iOS can do that already without any extra software. iWork is free on new iPads, and costs $10 per app for iPads purchased before October 2013.
In other words, Office for iPad requires you to pay for Office 365 every year, not just once. Adobe's done the same to its Creative Suite, and I suspect it's a change the cloud will allow software vendors to apply widely. Software will be like cable TV in that you'll never stop paying for it, and the price is likely to rise every year once you're hooked.
Even though Office for iPad is free in that context, it's not as compelling an app as it should be. Microsoft has been in the Office game for more than 20 years, nearly 30 if you count the DOS versions, and its mobile Office should be better than Apple's much more recent entry. It's not.
The good news is that Word and Excel are quite competent. The bad news is that PowerPoint is overly limited, and Microsoft's insular approach to file management and lack of features like local sharing against using it as your default iPad office editor.
Is the glass half full or half empty? That's a hard question to answer from this first version, but at least there's now water in the glass.
This article, "First look: Office for iPad is a mixed bag, but a good first step," was originally published at InfoWorld.com. Read more of Galen Gruman's Mobile Edge blog and follow the latest developments in mobile technology at InfoWorld.com. Follow Galen's mobile musings on Twitter at MobileGalen. For the latest business technology news, follow InfoWorld.com on Twitter.