Remember that the updates are OTA, so it could come out during that time, and not later. (Normally phones already manufactured before the final firmware is done have to be re-flashed before packaging, but Nokia might not do that).

The finnish operators say they will have the phone last or second last week of october. Usually this means retailers will have the phone a week or two before. (Retailers get first dibs). And Nokia usually release phones first or close to first in Finland.

I'd say mid-to late october is reasonable.

I wonder if Nokia delayed the release from early oct to late oct to build more devices & convert a few more production lines to the N900 because of how much more interest it has generated than what they thought?