A single blog would be better because what matters most is the story line or content. Explain about SFI and TripleClicks and how both are connected. Try to make it simple and easy to understand. Place 1 or 2 TripleClicks banners and do not forget to include your referral links to join SFI and TripleClicks (which you can obtain from the 'My Gateways' tab in the Affiliate Center).
Hope that helps with your decision and I wish you the best.
