What's the difference between Vimperator and Pentadactyl?

I am the project founder and still main developer of Vimperator. I have summarized my own perceived differences between the two projects here:

http://code.google.com/p/vimperator-labs/wiki/VimperatorVsPentadactyl (Project moved to github, a clone of the link: http://www.wikivs.com/wiki/Pentadactyl_vs_Vimperator)

Please read the whole page, but if you really need a short summary, because you just wasted time fighting Pentadactyl's complexity ;), here it is:

• Vimperator: The main focus is on usability, simplicity, stability and design while still preserving a powerful, modal browsing experience influenced by Vim.
• Pentadactyl: The aim is to create a complex beast, where hackers with too much free time can do any (un-)imaginable thing. Also focuses more on 1:1 Vim compatibility.

Hope this helps a little. I am sure both projects have their target audiences.

Maybe the FAQ section on the page you linked to could be helpful, in particular http://5digits.org/pentadactyl/faq#faq-differences and http://5digits.org/pentadactyl/faq#faq-fork .

The main difference is that Vimperator's most active developers have moved on to Pentadactyl. More qualitative changes may be found in the change log, but essentially add up to what we consider more active and thoughtful development.

Among the most visible differences, as of Pentadactyl 1.0, are more extensive Firefox 4 support, significantly better startup time and completion performance, considerably better :sanitize and private mode support, a greatly improved incremental find implementation, major improvements in Ex command parsing (including the ability to separate commands with | and split long commands across lines), conditionals (:if/:else) in configuration files, greatly updated documentation, and a number of bug fixes.

I can not say anything about the politics behind both projects, but here is what I think/have found out about both the projects:

1. Development Activity: Both projects have pretty much same amount of commits in last couple of months. As for quality and impact of each commit, I can't say much without checking the code, but from commit messages it seems to be quite similar too. [pentadactyl is always one or few version behind the Firefox releases]

2. Usability: For average user, Vimperator seems much easier to use, while Pentadactyl has a steeper learning curve but would feel very similar to vim users[1].

   2.1. Keymapping: The options and keymapping in Vimperator are much easier to remember for average users, for instance, to show menu bar, in vimperator you can simply :set gui=menu (substitute 'navigation' for navigation bar, 'tabs' for tab bar etc.) whereas in pentadactyl it is :set go+=M or :set guioptions+=M(a single character for each item which is also case sensitive)

   2.2. Customization: On the other hand, you can customize a lot more options in Pentadactyl then you can do in Vimperator. Taking our previous example, in Pentadactyl you can turn on and off bookmark bar, status bar, side scrollbar, bottom scrollbar and lot more using the same method as mentioned above, whereas Vimperator supports much less customization.

3. Design: Vimperator has a much more modern look than Pentadactyl.

Depending on what is important to you, both projects are good, if you don't care about aesthetics too much and are willing to spend some time learning the exact commands (or look them up in help, which is pretty simple to navigate) but want lots of customization options, or if you are looking for more vim-like experience, Pentadactyl is for you.

On the other hand, if you are an average vim user who wants to turn their browser experience to keyboard use only but don't want to spend too much time learning Vimeperator is for you.

[1]: Basic functionality is similar in both, like open pages, going back in history, closing tabs etc. it's the other features that I am talking about.

[2]: Vimperator may have options hidden deep down to enable/disable other gui options, but even if they exist, they are not as visible as Pentadactyl.