Mainstream Minerals Corporation : provides a Corporate Update “Gregory Gibson appointed as Chairman of the Board of Directors“

Winnipeg, Manitoba - November 7th, 2012

Mainstream Minerals Corporation (TSX.V: MJO)(the "Corporation") or ("Mainstream") is pleased to announce the appointment of Gregory Gibson as Chairman of the Board of Directors and provide a brief corporate update following the Annual General and Special Meeting of Shareholders recently held on October 25th, 2012. Following the election of all of the proposed director nominees, the Corporation's Board of Directors now consists of Gregory Gibson, Steven McIntyre, Dave Reid, James Darcel and Michael Romanik.

Gregory Gibson - Chairman of the Board of Directors

Mr. Gibson is currently the President, Chief Executive Officer and a director of Northern Gold Mining Inc. He was the President and Chief Executive Officer of Trelawney Mining and Exploration Inc. Under Mr. Gibson's leadership, Trelawney discovered and advanced the multi-million ounce Côté Lake Gold Deposit in Northern Ontario and then successfully negotiated the sale of Trelawney to Iamgold Corp. for $585-million. Mr. Gibson has over 30 years of experience in the mining industry as a mine manager for gold and copper mines in Australia, a nickel mine in Timmins, Ontario, and a gold mine in British Columbia. Previously he worked for JS Redpath, Dynatec Mining Ltd., Yilgarn Star Gold Mine and Copper Mines of Tasmania in a variety of operational capacities. He is presently a director of several junior mining companies.

Officer Re-Appointments

After the Annual General and Special Meeting of Shareholders, the following individuals were               re-appointed as officers of the Corporation:

Michael Romanik: President and Chief Executive Officer

Ray Préfontaine: Chief Financial Officer

Lisa McCormack: Corporate Secretary

Corporate Update

Mainstream President and CEO Michael Romanik stated: "We are thrilled to have been able to attract Mr. Gibson, Mr. McIntyre and Mr. Reid to join the Board and participate in the Corporation's future success. I would like to take this opportunity to thank outgoing directors Dr. Andrew Nevin, Neil Sullivan and Kyle Picard for their many years of dedicated service to the Corporation. Finally, I would also like to officially welcome the new members of the Board of Directors."

Newly appointed Chairman Gregory Gibson commented: "A strategic review of Mainstream's current portfolio of properties is underway. We will also be evaluating other opportunities that will add to the Corporation and allow us to increase shareholder value."    

About Mainstream Minerals

Mainstream Minerals Corporation is a mineral exploration and development company focused on precious metal mining properties with economic potential, with the aim of possibly bringing such properties to commercial production. With a portfolio of six projects located in the Birch-Uchi Greenstone Belt, Red Lake Mining District, the company is well positioned to take advantage of the resurgence of exploration and development activities in this prospective belt located 80 kilometres due east of the main Red Lake Greenstone Belt. These six projects cover an area of approximately 28,600 acres and host several known gold occurrences and past producing mines. Other projects include the Rowan Lake Project on the Cameron Lake-Pipestone Fault in the Kenora Mining District, the West Keefer Claims located in the West Timmins area in north-central Ontario and the Casa Berardi Claims in northern Québec.

MJO Shares Outstanding: 65,102,130
ON BEHALF OF THE BOARD

Signed "Michael Romanik"
Michael Romanik, President & CEO
[phone]
[e-mail]
www.mainstreamminerals.com

This news release includes certain forward-looking statements concerning the future performance of Mainstream Mineral Corporation's business, its operations and its financial performance and condition, as well as management's objectives, strategies, beliefs and intentions. The Company does not intend, and does not assume any obligation, to update these forward-looking statements. Forward-looking statements are frequently identified by such words as "may", "plan", "expect", "anticipate", "estimate", "intend" and similar words referring to future events and results. These forward-looking statements represent management's best judgment based on current facts and assumptions that management considers reasonable. The Company makes no representation that reasonable business people in possession of the same information would reach the same conclusions. All forward-looking information is inherently uncertain and subject to a variety of assumptions, risks and uncertainties, including the speculative nature of mineral exploration and development, fluctuating commodity prices, competitive risks and the availability of financing and as described in more detail in the Company's recent securities filings available at www.sedar.com. Actual events or results may differ materially from those projected in the forward looking-statements and readers are cautioned against placing undue reliance thereon.