The vBulletin importer has extensive changes, fixing issues including:
Double UTF8 conversion and text handling issues are now resolved
Performance is dramatically improved for the vB5 importer
vB4 blog attachments are now handled (and in fact, importing from vB4 with blog into XF2 will actually recover the vB3-blog attachments that went missing when you upgraded to vB4!)
Previously missed content is now fetched
vB5 conversations are properly imported
Improved compatibility with schema.org standards
Image resizing errors fixed
Improved handling of legacy user upgrade purchases
Improved purchase cancellation handling
Added missing code language phrases
Improved keyboard shortcut handling
Fixed canonicalisation of URLs under IIS
Fix for webkit browsers related to h-scroller
Display of attachments in quick thread fixed
Fixed handling of AJAX filtering when no results are returned
Fixed Tweet embed handling
Fixed potential infinite loop in the colour picker system
Improved IE flexbox handling
Fixed reference to non-existent post_above ad position
Support for setting javascriptUrl in config.php
Fixed post edit history handling
Handle spam-cleaner-deleted users better
Fixed error relating to moving deleted/moderated posts
Added an index on xf_conversation_master.start_date for improved performance
New filters zerofill() and pad() available in the Templater
Twitch media embed handling improved
Fixed calls to CONVERT (%s USING utf8) to use utf8mb4 when necessary
Fixed invisible thread prefixes imported from XF1 to be visible
Add-on releases can now include .htaccess files
Fixed select-to-quote tooltip for mobile browsers
Update to Froala editor 2.7.4, lots of related bugs fixed
See the resolved 2.x bug reports forum for further information.

PAGE_CONTAINER
app.less
app_body.less
approval_item_resource_version
base_custom_field_list
bb_code_preview
conversation_message_macros
core.less
core_hscroller.less
core_labels.less
core_tooltip.less
editor_base.less
forum_post_quick_thread
google_analytics
helper_action
helper_criteria
helper_user_search_criteria
import_index
import_step_config_vbulletin
log_sitemap_list
log_spam_cleaner_list
log_spam_cleaner_restore
member_stat_edit
message.less
node_list.less
option_macros
option_template_registrationWelcome
payment_profile_paypal
post_macros
thread_view
tools_rebuild
user_title_ladder_list
user_upgrade_active_downgrade
user_upgrade_manual
widget_members_online