Another group that will notice are the money man. Wether it be SD, JS or anyone they might wish to accept investment from. Football clubs with the potential of ours are rare. In my opinion, SD was only ever going to stabilise the club and prepare it for further investment.
Excellent point, it reminds the owners/prospective investors/sponsors/etc etc etc that we're worth their time, effort and money.
There's another point that the resident miseries are missing, sadly they're taking the phrase 'message to the world' entirely literally. It's actually a message to the football world of which we're all a part. It's possible there are players in that world who will know Sunderland are watching them with a view to making a bid .... and a massive gate, in this game, could quite easily be part of the reason a player would want to sign for the club.
No big deal but it might just make the difference we need at the end of the season.