For an HTML email, how can I set up two side-by-side column divs? - - Or is this unacceptable for email clients?
You don't use <divs> to construct a html email, use a simple two column table. Keep the width to about 600px wide in total.
We all long for the day when <div> tags and basic CSS styling will be supported by all the major email clients, but alas the time is not now. At this point, things like position or float aren't supported by outlook or lotus notes, so that pretty much nullifies using divs for structure at all. You can still use them within table cells for universal styling purposes (or to use them in place of <p> or <br> tags) but it's not a good idea to use them for anything else, unless you have a one-column layout.
** EDIT: Campaign Monitor keeps a CSS compatibility chart that is extremely helpful http://www.campaignmonitor.com/css/ **
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