Bent has joined the Black Cats on a four-year deal for an initial £10m fee rising to £14m, after protracted negotiations between the two clubs were concluded yesterday.
The transfer exceeds the previous club record £9m paid for Scotland international goalkeeper Craig Gordon from Hearts two years ago.
Bruce said: Darren is a fantastic player so Im thrilled to have him at our football club.
He has pace and is a natural finisher so he will be a great addition to our strike force, giving us new attacking options.
You just have to look at his goalscoring record in the top flight to realise Darren is a huge signing for this football club.
Credit must go to the chairman, chief executive and our club secretary for the hard work that has gone on behind the scenes to seal this deal has been incredible but that just shows the commitment there is here to take this club to the next level.
Bent should make his Sunderland debut at Hearts on Saturday and he could be joined by former West Ham defender Neill.
The Australia international became a free agent last month and Bruce will try and secure the experienced right back on a one year deal.
Its a measure of Sunderlands increasing financial clout in the transfer market that they are able to offer Neill, who was on a reported £72,000 weekly wage at the Hammers, a deal to bring him to Wearside.
The 31-year-old right back rejected a one year contract to remain at Upton Park after the club insisted he took a 50 per cent pay cut. Bruce is desperate to recruit an experienced right and met Neill at the Sunderland team hotel prior to Tuesdays match at Peterborough.
Neill has 50 caps for his country and would offer Bruce the kind of no-nonsense defensive presence the manager is known to favour.
His ability to play across the back four will not however, stop Bruce from attempting to bring in a centre-half and he retains interest in Richard Dunne and Sylvain Distin.
Bruce has earmarked Dunne as a potential Black Cats captain and admitted he expects to bring in a new skipper rather than appoint from within the existing squad.
I will probably not make a final announcement until the transfer window closes, said Bruce, who has handed Danny Collins the armband during pre-season.
Collins is determined to persuade the manager his six seasons on Wearside and affinity with the Sunderland fans who awarded him backto- back player of the year awards makes him the ideal choice.
Of course I want to be captain.
I see myself as captain material and I love to keep the armband given a chance,
said Collins. Its been mine through pre-season and Im in no hurry to give it up.
I understand what playing for Sunderland is all about so that is a good base for any captain.
If the manager wants me then Id be honoured but playing every week is the main thing.
And Collins looked forward to playing alongside Bent after having the job of marking him last season.
The players had a meeting and we talked about where we wanted to be and the target was nothing lower than tenth next season, he said.
So we know what were aiming for and hopefully Darren and the other new boys can take us to that next step.
I remember both games against Spurs last season and I had a good battle with him, I enjoyed it.
He works the channels well, keeps defenders on their toes and is good in the air.