Every blog has its own effect. Cast your your nets in the waters you never can tell which one will give you the greatest harvest. I will say make seperate blogs for SFI and TripleClicks and maybe for each gateways and since it will be good to be creative, change your blogs from time to time, this imparatively means you could do a single blog for both sfi and TripleClicks with a demarcation and putting their links beneatn each blog. Which ever is good but i personally think separate blogs is better.
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