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If you have any more to add to this, I'm sure the rest of the community could use it, as there have been many a webmaster that have deleted the default account.
In hindsight, this account should not be deleteable from the user admin for obvious security reasons, but more commonly for the stability of the site and module calls that rely on uid=1.
I would also like to point this out to the documentation team to take note and place a snippet in the install notes for users asking them not to delete the account to save from unforeen permission problems with other modules and core functions that rely on it.