after importing from iphoto 09?
True if you actually do Import your old library - that is a BIG NO NO - Never import one iPhto library into another one - it does not work and creates a masive mess
to move from iPhoto '09 to '11 on the same system simply backup your iPhoto library and install iPhoto '11
To move from an older system to a new system Connect the two Macs together (network, firewire target mode, etc) or use an external hard drive formatted 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.
LN