The "Infinity" by ""designcoral." [http://profiles.wordpress.org/designcoral] is not the same "Infinity" as created by Theme Trust [http://themetrust.com/themes/infinity] however my Manage Themes is telling me an update is available.
If you have Theme Trust's Infinity installed you will overwrite it, loose it and all modifications you may have made if you follow the instruction to update.
This issue points to a fundamental problem in the naming of WordPress Themes. Once a theme name is used WordPress should allow it to be avaialbe to other theme creators OR WordPress should create an update that is able to distinguish
I have a paid Theme Trust theme installed called "Infinity" but WordPress is notifyingm that an update is avaiable for that theme. However, when I checked the theme it linked me to a one produced by "designcoral." If I were to install the update I would overwrite the Theme Trust Infinity theme [which as an aside, is a far superior theme.
Happily I checked things out before automatically following the instruction to update. However, now I will forever had ignore that update informatin.