I am "the guy". I have a Yahoo account (currently inactive) and an MSN account.
The biggest issue I have with the two "competitors" to Google, and I use that term loosely, is that they don't have nearly enough inventory to sell me to make it worth my time. Example: I have bought approximately 65,000 clicks in from Google in this calendar year. Over the same period, Microsoft (which plain lacks a display network, where I get most of my clicks) has managed to find less than 1,000.
Yahoo was similarly terrible back when I used them, and in addition to charging me too much for not enough, they routinely borked their conversion counting, causing me to believe my spending on them was profitable when it was, in fact, not. After I audited their numbers and discovered their lack of facility with math, I stopped advertising with them.
I had similar experiences. Also when I last used Yahoo they had a "minimum spend" restriction, which meant that if they were unable to find you enough traffic, they'd charge you any way!!?! I closed my account after a couple of months of them charging me because they couldn't deliver enough traffic.
You should definitely always contact google by phone though. Email never works well.
It depends on the market he's working, Yahoo does not have the same volume that google has and chances are that he does not get the same returns on his time there because of that. Niches are tough. Once you have one it is a little cash cow but if anything bad happens then you find out fast that a niche is fragile. A single competitor that works a bit harder than you, a drop in your traffic... Chances are that somebody is simply outbidding him.
He's spent 12K on ads to date according to the piece, that means that he's had to sell at least 400 licenses to break even.
Apparently his market is to sell $30 software to create bingo cards, hardly a mainstream market.
