A picture is worth a thousand words
...but don't use those words in the picture.
Let me explain. I look at a lot of IM'ers sites (not just here but in the wide world of the internet) in order to well, learn from. One thing that surprises me is how often people use pictures that are actually just text.
This is an example:
That picture was actually over 5000 pixels long...
Now I don't know whether its a lack of knowledge or people have been sold a crappy site, but using an image for text makes NO sense.
Why? Because of on page SEO.
With an image you add two things that help with SEO, a Title tag and an Alt tag.
A Title tag is what people will see when they hover over the image (try it on the one above).
An Alt tag (for alternative) is what people see when the image cannot be shown, like with screen readers or images turned off.
N.B. don't try and cram keywords randomly into these, as that can be seen as spam, if you can't find a suitable, relevant keyword for the picture, just put something basic.
Both of these are great and can (should!) be used for SEO - a picture of a muscled arm, Title tag = The post title or something like "Big muscles can be yours with ProductX!", Alt tag = A muscled arm picture.
Search engines like Google look at these tags and use them, but if you have text within the image the robots (bots, spiders) that search engines use CANNOT READ the text. So if you have some brilliant SEO keywords in that image they are WASTED.
Also, using images for text slows a page down, especially on slower connections, whilst the image loads.
But with text, all the words there are potential keywords (depending on what it says of course), so it makes sense to use just text instead of text within an image, in order to help boost SEO.
On the flip side, im not saying don't use pictures, just use them appropriately. You should use pictures for things that enhance your text copy such as a muscled arm on a muscle gaining website, or that provide info like a chart or something like that, but please don't just use it for text copy, you will only be hurting yourself in the long run.
As a little bonus for actually reading this blog post, when using an image, try and give the image filename something human readable: i.e. a_muscled_arm.jpg or productx.jpg rather than DSC00253.jpg as more and more traffic is being gained from Google Images and similar services.
Disclaimer - I'm not saying WA users do this, merely highlighting that this practice occurs and should be shied away from. Dean.