The WYSIWYG editor has a new (experimental) image dialog that simplifies the insertion and edition of images. The new dialog is currently disabled by default but you can enable it from the WYSIWYG Editor section in the Wiki Administration: look for 'xwiki-image' in the drop down of disabled CKEditor plugins and uncheck it then save.
The new image dialog is integrated with the Image Style Administration section so users can apply image styles defined by an administrator. Checkout the CKEditor Integration documentation for more information.
