Easy peasy. Untar, overwrite files. Login again. Upgrade complete. That is how I like upgrades to work.
Not much new in this version, but there is a security upgrade, which is what prompted the upgrade.
I am also playing with gallery 2.1 install somewhere. Might be moving to it soon. 2.1 still seems slow to me, and that sucks. I have also figured out how to set it up so the urls match my current install (using the url_rewrite module). That was also a huuuuuge stumbling block. Unfortunately some of the URL’s still; aren’t to my liking.
Gallery 1.5.3 pictures url: http://www.domain.com/gallery/albumname/MG_8387
Gallery 2.1 url:http://www.domain.com/gallery_2_1/albumname/MG_8387.jpg.html
I want to get rid of the .jpg.html but so far haven’t figured that one out.