When Microsoft Office 2007 hit the streets, its new user interface--topped by a super-sized toolbar called the ribbon--delighted some and frustrated many. Long-standing WordPerfect users will be relieved: The latest release of Corel's WordPerfect Office doesn't have similarly drastic user interface changes.

There's something to be said for WordPerfect's clean, no-nonsense blank page. While the suite keeps its traditional looks in the new X4 version, it does beef up support for both PDFs and Office 2007 file formats. Existing WordPerfect users will find the new version worth the upgrade, but Microsoft Office users will find few compelling reasons to switch suites.

WordPerfect Office is cheaper than Microsoft Office, but not by much. Although the Standard ($299) and Professional ($399) versions of WordPerfect Office are about $100 off the list price of Microsoft Office, retailers like Amazon currently offer discounted Microsoft Office prices that bring it within a few dollars of WordPerfect Office, effectively erasing the price advantage.

I looked at WordPerfect Office X4 Standard Edition, which includes the WordPerfect word processor; the Quattro Pro spreadsheet application; Presentations; the Visual Intelligence data analysis software; WordPerfect Lightning, a Web-connected note-taking app; and WordPerfect Mail for managing e-mail. While WordPerfect's comfortable interface hasn't changed much in nearly a decade, the office software market has. WordPerfect is now a very distant second to Microsoft Office. In this position, WordPerfect's most important feature is offering compatibility for file formats from other programs. So how well does it play the compatibility game?

The core WordPerfect Office applications support an impressive range of file formats, including Open Document Format (ODF), the very oldest WordPerfect versions, and a few ancient Microsoft Office formats (Word for DOS, anyone?) that even Microsoft doesn't support anymore. Most important, WordPerfect Office can open the latest XML file formats from Office 2007 (those with the -x extensions, like .docx, .xlsx, and .pptx).

In fact, WordPerfect seems to have an easier time dealing with the new Microsoft Office file formats than with the traditional ones, and often imports them with fewer glitches. WordPerfect's compatibility is extremely good--but not perfect. Most of the Word documents I tested imported without a hitch, although I had problems with richly formatted documents, such as missing or mangled pictures. Overall, WordPerfect's support for Office file formats is good enough that most workers won't face a headache when exchanging documents with their colleagues.

One of the most hyped new features in WordPerfect Office is its PDF support, which goes several steps beyond what Microsoft Office provides, including a host of additional options for configuring PDF creation, allowing an author to control details like font subsetting, picture compression, PDF compatibility level, and even password-protecting a document.

Still, WordPerfect's ability to edit PDFs is overstated. Yes, WordPerfect does provide the useful ability to open PDF files and convert them to WordPerfect documents. But in some cases, this process fails (ending with hopelessly scrambled text), and in other cases it works but still leaves you with an altered layout. So the open-PDF feature is a great way to rescue text out of a document in a pinch, but it's never as good as working with the original files.

Impressively, however, this WordPerfect Office introduces an ability to use optical character recognition when attempting to read PDFs that contain scanned-in images instead of text. Once again, it's not perfect, but no other office suite offers anything close.

Most of WordPerfect's best features have been in place for years--for example, legal professionals, government workers, and technical writers love features like Master Documents, which let you build long documents out of separate files. WordPerfect is also legendary for its Reveal Codes feature, which lets you edit and rearrange your document's low-level formatting instructions, giving you fine-grained control over what's taking place. Another longstanding favorite is the Preview option, which lets you browse the full content of a document in the Open dialog box before opening it.

But in other areas, the level of polish in WordPerfect Office falls short of Microsoft Office. For example, WordPerfect still forces users to click the status menu to get an updated word count. (Word keeps the word count perpetually updated.) And who can explain why WordPerfect still limits users to nine open files at a time, and why the status bar shows the number of the page you're working on but not the total number of pages in the document?

Hard-core Excel and PowerPoint users are also likely to be a bit disappointed. Although Quattro Pro's charts have compared well with Excel's clumsy graphics for years, they can't compete with the jaw-dropping eye candy introduced in Excel 2007, such as the latter's new chart-rendering engine and data-visualization tools. WordPerfect Office makes a half-hearted attempt to compete in this area with its new Visual Intelligence program, which helps create chart data in complex spreadsheets and databases. This tool, though, would be better off as an integrated feature in Quattro Pro.

Price-conscious buyers are more likely to look at completely free competitors such as OpenOffice.org and IBM Symphony. Nevertheless, WordPerfect keeps its best features and adds enough new ones to keep current users satisfied--and its increased compatibility with Microsoft Office is worth the $160 upgrade fee.

--Matthew MacDonald