Sure - No Importing involved - NEVER import an iPhoto library into another iPhoto library - it does not work
-- Connect the two Macs together (network, firewire target mode, etc) or use an external hard drive formed Mac OS extended (journaled) and drag the iPhoto library intact as a single entity from the old Mac to the pictures folder of the new Mac - launch iPhoto on the new mac and it will open the library and convert it as needed and you will be ready move forward.
I've added to the Snow Leopard library the Lion's Masters folder and the mess is absolute, specially when you have around 50k photos...
In addition to NEVER importing one iPhoto library into another iPhoto library ayou also NEVER make any changes of any sort to the content or structure of the iPhoto library - there are no user servicable parts in it and any changes you make will cause problems and possibly data loss
LN