I think people have grown accustomed to banners to the point where it no longer feels like a "hard sell" Although that obviously comes down to what the banner is, positions, size etc.

A text link is more leading, CTR higher and conversion better but it's more of a deceptive process.

When you have people pushing services within a industry i think text links would do better. but It's kind of subjective to how good the content is and if the reader knows or not if it's a sell.

I've bought SEO services off Matt Woodwards site based on his tutorials, i knew it was affiliate link, but that didn't bother me, because 1. he's open about it and 2. he provided good quality content to provide it's worth.

On my blog If i start pushing women's boots reviews down people throat, without genuine picture of someone wearing them it's not going to make a sell.

If I spin some celebrity fashion content and link to an item they are wearing, it's more likely to convert.

I really depends on the niche and the content you create.

Read more from Martin @ //www.martiniharris.co.uk/