Allow "batch updating" during import

I think the import process can be streamlined if we can integrate the batch updating with the import process. Here's a use case:

I am importing 500 records that only contain name and address data. These contacts all need specific settings for each of my many custom fields. Currently I have to do the import, remember to tag them with a new tag (If I forget this step I'm screwed), then once the import is complete search for that tag, and do a batch update.

A much more streamlined workflow (and this is how it works in Kintera), would be to add a new step in the import process, right before the final step. CiviCRM could ask me to set values for additional fields.

I'm visualizing a JSified form where at first I see only a single-select box of field names. After I choose a field it shows me the appropriate widget (checkboxes, state select box etc.). On the next row I can then select another field.