For $20 you can buy the BulkReg module on SnowCovered.  Just get your user data in the defined format in the documentation and off you go.  I used it for several hundred users with no issues.  It can also perform bulk updates/deletes too.  The only issue arises if you have profile properties outside of the default ones you wish to populate.  In that case you will need to write custom SQL to populate those once the core user data is in.

Please test carefully the below before you try it on an installation you care about.  I did test this but ended up not having to use it on a live site, so I never signed off on my own QA testing.  Buyer beware etc....

Assuming that the custom profile property exists and is called "AreasOfInterest" that SQL might look something like the below for a user id of "test".  Obviously this could be refined to pull values from your user data.

insert dbo.UserProfile (userid,propertydefinitionid,propertyvalue,propertytext,visibility,lastupdateddate)
select u.userid,
          (select d.propertydefinitionid from dbo.ProfilePropertyDefinition d where d.propertyname = 'AreasOfInterest'),
          'this is the value','this is the text',2,getdate()
from dbo.Users u
where u.username = 'test'

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Shawn Duggan MCPD
BlueTango Software - Canada Web Content Management
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