It's a nice idea to raise the memory limit on the script side so the user doesn't have to bother about it - the only problem is when the limit set in the script is too low. For my conversion the 128M for PHP memory set up in install/index.php weren't enough, and it took me quite some time and sweat to figure out why changing php.ini still didn't provide me with enough resources to finish the conversion.

Proposed solution: Raise the value to at least 256M, or better yet, provide a flexible solution within the script. Most important of all, the user should be aware that the script may actually be reducing the memory available.