Thunderbird is the Mozilla Messaging Group's free and open source e-mail app for Windows, Linux and Max OS X. Version 3 (TB3) has been in public beta for a long time, and recently Release Candidate #1 was posted. Great strides have been made, yet the app still remains short of the perfect e-mail app for Macintosh users.
It was just about a year ago that I reviewed Thunderbird 3 Beta 1. I said that version 3 was becoming a viable alternative to Apple's Mail.app, and that's still true. However, it's one year later, and my personal expectation was that TB3 would not just become a viable alternative, but become the best mail application for the Mac. Regrettably, despite a boatload of additions and refinements, that goal, if it ever was a goal, has not been achieved.
Main Window (Red outlines denote UI enhancements)
Here's an overview of the situation. TB3 is a serious e-mail program for serious users. It has great flexibility and a myriad of options. It doesn't feel watered down like Apple Mail.app. However, neither does it have a sense of refinement and coherence on the user interface side. That's part and parcel of what you get when hundreds of volunteers work on a project as opposed to a single person with a vision and a half dozen smart Apple software engineers.
Here are some examples. The default format for the new mail alert sound is .wav. Mac users, however, have a disk full of .aif files. Converting is trivial, but one shouldn't have to. Next, TB3 reads from the Mac OS X address book, but cannot write back to it. (This will be fixed in TB3.1.) Worse, TB3 boasts "smart folders," but they're nothing like what Mac users are accustomed to in the Mail.app. Instead, TB3 does something similar with customized views of a mail box, and smart folders simply means that all incoming e-mail from all accounts are conveniently grouped into the in box. As a result, after a year of work, things that any Mac user would expect to just work in 3.0 still aren't there.
That's not to say there haven't been terrific additions. I like the tabbed browsing of messages. Like Apple's Mail.app, setting up accounts is more automated. That is, I shouldn't have to know that Google's smtp server is smtp.gmail.com, uses port 574, and uses SSL/TLS.
Thunderbird 3 Features
There's a cleaner look, tabs, a tool bar, a full text search, and several different arrangement options for the various window panes, including the classic Mac OS X look. In addition, there's a manager for better handling of Add-ons.
One nice feature is the Attachment Reminder. TB3 scans the body of the message, looking for clues that that the sender may be planning to include an attachment. If it's not there when the Send button is pressed, TB3 will offer a gentle reminder.
Despite all the 2,000 fixes and improvements claimed, it's amazing to me that there isn't a better sense of overall design philosophy. For example, Account Settings, something that every e-mail user expects to find in the Preferences insists on being at the bottom of the Tools Menu. Also, there is a tiny, tiny icon at right side of the From/Date/Subject bar that defines which fields are displayed. It's easy to use, but a pain for a new user who might also expect to find that in the Preferences. I'll note, on the plus side, that once you find it, it's cool. The check boxes take effect immediately. That way you don't have to go into and exit preferences to see the result.
This is a handsome demonstration of how TB3 prioritizes functionality over intuitiveness. As a result, power users will love Thunderbird, and Mail.app users looking for something better, without knowing what better really means, may not like it at all.
And yet, there are surprising lapses in the completeness for power users. For example, in the Preferences -> Display, one can define the background color for the body of messages. Fantastic. The Apple Mail.app, around since the days of Mac OS X 10.3 (Panther) still can't do that. And yet the selection box isn't a color palette; instead it's a limited 7 x 10 grid. So you might be frustrated that you can't get just the color you want. That smacks of a developer/contributor who didn't understand something key about Mac OS X APIs or was constrained by cross-platform code. In fact, when an app is designed to be cross platform, little things like this can often get in the way. David Ascher, the product manager for Thunderbird told me that TB3 is indeed written with Xcode and C++ (Not objective-C). I'll guess that that plus the cross-platform emphasis could explain some of API interface issues that will keep TB from ever winning a WWDC Apple Design Award.
Prefs - Text Background Color
Another lapse is the that the default toolbar doesn't contain the View option. Worse, in the toolbar settings, it's scrolled off to the bottom. This is a key popup whose customize option is what allows the user to approximate the Mail.app's smart folder view. Such an important item shouldn't be buried, especially when the term "Smart Folder" is bandied about by the Mozilla Group so extensively.
Yet another lapse is the inability to do a QuickLook on an e-mail attachment. That's not invoking the best that Mac OS X APIs have to offer.
Finally, for an app of this kind of power and customizability, there needs to be a full PDF manual available. There is not. As a result, the new user looking to fully understand everything will have a tough time. You either keep it simple to the point of not needing a manual, like the Mail.app, or you provide extreme power and customizability -- and commit to a manual.
The bottom line is that TB3, at RC1, is almost ready to be released, and provides a comprehensive and powerful e-mail tool that is not only cross-platform, but also looks fairly good in its native instantiation on a Mac. Many users will find it to be more grown up in some ways than the Mail.app. Others will find it too complex and the lack of a formal manual troublesome. What stood out for me, however, is that the developers weren't able to focus on what's really important to Mac users -- a super clean, intuitive UI that invokes the best in Mac OS technologies. As a result, I believe that most Mac OS X users at home using the Mail.app will be happy to stand pat for now. That includes me.