This was back in 2009, so we were still fitting square pegs in round holes in the "3rd midfielder" spot, behind Fabregas and ahead of Song - who played his best football that season imo - just shielding the back four. Cabaye was a bit more of an aggressive forward player back then, making forward runs from deep a la vintage Lampard but still filling the gaps in CM, he plays a little more tamely at Newcastle, but it suits them.
Arteta/Chamberlain and Wilshere are neither here nor there. We signed the latter two only last year, and Wilshere was an Arsenal youth that we probably weren't seriously thinking of promoting as soon as we did - think Jack forced Wenger's hand a bit with those early mature performances after Diaby got crocked, and anything that can get Arsene/the Board out of spending money sounds good to them. We definitely could have used Cabaye this past few seasons, instead of Denilson/Diaby, don't tell me otherwise. Whether or not he would have reached another level here instead of at Newcastle, is of course up to debate, but I think he would have been a first team starter for us, even last season.
In any case, it's not like I think he's world class or anything, but we would have had a better midfield the past few years with him in it, that's for sure. Now it's too late. Newcastle have no reason to sell - this season, at least.