The correct URL for that blog is http://www.anythingpalmeiras.wordpress.com/ as no WordPress.com blog URLs ever contain "www". I am using a Firefox 3.6.8 browser and I'm viewing the blog which is wearing the MistyLook theme. What I see is that all the widgets are now centered.
It appears that the theme has been coded left align the contents in widgets and we cannot edit our themes or templates here at wordpress.com. http://en.support.wordpress.com/themes/editing-themes/
You may be able to change this by purchasing an annually renewable CSS editing upgrade or not. I don't know as I have not tried. If you are considering purchasing the upgrade, you can go to Appearance > Edit CSS. There wordpress has provided a preview function where you can try before you buy.
Please note that since there is no official Staff support for the CSS upgrade, and precious little Volunteer support, it's not recommended that buy the upgrade unless you have at least moderate understanding of HTML and CSS because you must be prepared to do the work on your own.