I'm not sure what you mean when you write that the dates/tags are not consistent after import from iPhoto. Do you mean that those attributes are wrong in the metadata? Or that you have a folder structure organized by date, and the photos are in the wrong folders (but with correct metadata)?

If your situation is the latter, I had a similar problem when I moved from iPhoto to Aperture. At the time I wrote a little Applescript to help me reorganize. I won't post it unless you'd like to see it, as the code is very specific to my situation and probably won't be helpful to you. But in general, my approach was this:

1. Create a set of folders by year (i.e. "2007", "2008", "2009")
2. Identify a set of photographs to move (in my case the contents of a single large folder containing everything from iPhoto)
3. Loop over each photograph, get the date from the EXIF data, and move it into the appropriately dated folder.

That sounds conceptually simple, and writing the script that way is fairly straightforward since Aperture has a good scripting dictionary. Remember that Aperture has both **folders** and **projects**, which is a slightly different nomenclature from iPhoto albums. You'll need to decide how you want to use projects and folders for organization. I use projects named by Year-Month, for example, with one giant folder of Archives and one folder of Current photos.