Wenger has had to endure one of the most testing spells of his 16-season tenure at Arsenal this season, including a Capital One Cup penalty shoot-out defeat to npower League Two side Bradford. However, there is now genuine optimism for the second half of the campaign as the Gunners are now back within striking distance of the top four and ready to tackle Bayern Munich for a place in the quarter-finals of the Champions League.
"My hopes (for the new year) are that the win (over Newcastle) will give even more confidence, desire and ambition to our team, and that 2013 will confirm we are a great team," Wenger told Arsenal Player.
Theo Walcott bagged an impressive hat-trick against Newcastle and is relishing a chance to shine in his preferred central attacking role.
"I have worked with Theo for seven years and the fact that he had an exceptional game against Newcastle will not influence me more or less - if he had played a disastrous game, I would still have wanted him to sign with the same intensity," Wenger said.
"It is good that he gets rewarded for his effort and for me that is more important."
Walcott will return to his old club tomorrow, along with midfielder Alex Oxlade-Chamberlain, who was also on target against Newcastle.
Wenger is likely to rotate his squad at St Mary's, but could well opt to unleash Walcott down the middle once more.
"I like the fact Theo can play through the middle because it gives us more opportunities to do that and more possibilities to change from game to game. I will do it again," Wenger added.
Walcott came through the youth ranks at Southampton before joining Arsenal in a big-money move as a raw teenager in January 2005.
The England forward made a subdued celebration after he scored in the 6-1 win over the Saints at the Emirates Stadium in September, and is clearly relishing the opportunity to return to the club where he was the youngest player to appear in the first team.
"It will be a very tough occasion against Southampton, but it is one I am really looking forward to," Walcott said on Arsenal Player.
"It will be a very special moment for me and Alex, and also for some of the fans to see us come back to the club."
Despite some positive displays, Southampton remain in the relegation zone after they drew 3-3 at Stoke in a match they had led 3-1, and were only denied victory by a superb last-gasp strike by Cameron Jerome.
Wenger is expecting a tough test of his side's new-found confidence.
"They are not comfortable (opponents), Southampton. I saw them against Fulham, and they played very well against Stoke," Wenger told reporters.
"Southampton are a team that has learned in the Premier League now. Usually you find in February or in January a different team to what you see in August or September."
Arsenal raided the Saints again last summer when securing Oxlade-Chamberlain in a £12million deal.
It has looked another sound investment, as the 19-year-old has developed quickly and since won full England honours, playing at Euro 2012.
Wenger feels Southampton deserve praise for their player development.
"It is down to the quality of their scouting, the quality of their coaching and education."
Arsenal, meanwhile, are reported to have tabled a £10million bid for Atletico Madrid striker Adrian Lopez and will also look to offload fringe players like Marouane Chamakh and Swiss defender Johan Djourou - who is reportedly a player of interest to German side Hannover - during the January window.