Ziff-Davis Publishing Co.'s Yahoo! Internet Life
goes monthly with its September issue, with the rate base doubled to 200,000. Ad rates will increase 29% to $6,050 for four-color and to $4,655 for b&w. It will offer subscriptions at $19.97. Separately, CMP Publications' rival monthly NetGuide
launches this month a distribution and promotion deal with 43 cyber cafes. Non-magazine sponsorship of the promotion costs $24,000 per year or $2,500 per month; InContext Corp. and US Robotics are NetGuide's
charter cafe sponsors. NetGuide's
circulation is 257,615 ; page ad rates are $12,500 for four-color and $9,500 for b&w.