Ozil, 24, completed what is understood to be a £43million switch from Real Madrid on transfer deadline day as Arsenal boss Arsene Wenger finally landed an addition of supreme quality.
Having come up against Ozil in action for England in their 4-0 defeat in the 2009 European Under-21 Championships final, Walcott is in no doubt of the impact he can have for Arsenal.
"It definitely shows a statement that we are ready to step up," said Walcott.
"We had a disappointing start to the season, but we have bounced back (with the win over Tottenham) and it is looking fantastic now.
"With the likes of Ozil joining the club, it is only going to boost everyone."
Ozil admitted he had not expected to leave the Spanish giants but revealed once it was clear he no longer figured in the first-team plans of Madrid manager Carlo Ancelotti following the world-record signing of Gareth Bale from Tottenham, he had no hesitation in moving on to a fresh challenge at Arsenal.
Ozil is now set to become an integral part of Wenger's team alongside Jack Wilshere, Walcott and Santi Cazorla.
"At the weekend, I was certain that I would stay at Real Madrid, but afterwards I realised that I did not have the faith from the coach or the bosses," Ozil said in an interview with the German Football Association's official website, www.dfb.de.
"I am a player who needs this faith and that is what I have felt from Arsenal, which is why I have joined.
"Wenger gives me the faith and I can develop further. I know what I can do and I know that I could make the grade with any club in the world because I am so convinced in myself, but if I don't feel people have faith in me, then that is why I had to leave and at Arsenal, I feel I have this fully.
"I am sure the new coach is going to develop me further and I am also really looking forward to playing in the Premier League."
Before Sunday's 1-0 win over big-spending Tottenham, Wenger had seen moves for Gonzalo Higuain, Luis Suarez and Yohan Cabaye all fail to materialise, and only secured the free transfers of Yaya Sanogo and Mathieu Flamini, before a loan move for Palermo goalkeeper Emiliano Viviano was completed on deadline day.
Although being signed initially as support for Wojciech Szczesny and Lukasz Fabianski, the 27-year-old Italy international fully intends to make the most of any opportunities which come his way.
"I think it is a good thing that there are other great goalkeepers here. It is a positive fight," Viviano said.
Arsenal had also been keen to bring in some more offensive cover and looked at a loan deal for Chelsea forward Demba Ba, but the Stamford Bridge club were not interested in reaching such an agreement with their rivals.