The outdated version of migrate.php is already available. I had just updated it so that we can use it for the latest version. Only some field names, table names etc are changed.

Step 1: Upload the wordpress files to the b2evolution directory (This is to keep permanent link as same)

Step2: Install wordpress, Use the same database as that of b2evolution.

Step3: Upload the script migrate.php to the folder wp-admin . Run migrate.php

Help with Permanent Link

The table wp_options contains a field, “permalink_structure” edit it and keep it in the way you want.

Some notes about the script : migrate.php

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Step1 :  You have to connect to the database.

Step2:  Remove the present contents of wordpress tables. It is better not to delete details of user. Otherwise wordpress admin may not be able to access the admin area after running the script.

Step3:  Import users and user meta data.

The table evo_users contains users of your present blog. Select it from evo_users and insert it into wp_users.

Step4:  Import categories.

The table evo_categories contains the category name. Import them to wp_terms.

WordPress handles categories using wp_terms and wp_term_taxonomy tables

Step5: Import the posts

The table evo_items__item contains the posts . Import them to wp_posts.

Step6: Establish category-Post relation.

The table evo_postcats contains the relation between posts and categories. We can import them to wp_term_relationship

This is the difficult part of the job, since wordpress handles category using 3 tables wp_terms, wp_term_taxonomy and wp_term_relationships.

Step6: Process the category counts, ie here we are counting how many posts per category

Step7: Import coments

We have to  import comments from evo_comments to wp_comments

In this way we can import posts, comments, categories, category-post relationship. We can settle permanent link issue by editing wp_options table.

Update on May 17th 2009:
One of the clients asked whether I can fix tags and authors. I have updated the script to import tags and authors.
So now the script will import posts, comments, categories, category-post relationship, tags tag-post relationships and authors. We can settle permanent link issue by editing wp_options table and .htaccess file.

For the script, migrate.php , please contact gsh [dot] james [at] gmail [dot] com .  We will be happy to assist in importing your b2evolution blog to wordpress. [Paid Service]

Price for the script : 30 USD
Price for assistance (doing it by myself) : 50USD

Linkedin profile: http://www.linkedin.com/in/gishajames

Thanks