You may have been confused if you read this morning’s Facebook headlines. The Wall Street Journal says some big ad buyers are questioning how effective their Facebook ads are, while CNET is reporting that Facebook won’t take some advertisers calls when they try to buy ads.

Which report is right? Or are they both right? And does it matter? Probably not, if you’re thinking about buying shares of Facebook after it goes public later this month. What matters for potential investors is that Facebook once again appears to be having trouble demonstrating that it can sustain growth from advertising which, to date, has accounted for about 85% of Facebook’s $4 billion in annual revenue.

But appearances, according to experts interviewed by ReadWriteWeb Wednesday, can be deceiving.