Openlayers marker choice per node

Hi guys,

hope you can help me out with a question about setting markers on openlayer maps for certain nodes.
When using gmap it is possible to choose a marker which will represent that node on a map. That marker type is associated with the node and will show up e.g. on maps created with views.

Now my question is, how do I realise something similar with openlayers?

The only solution that comes to my mind is to create a vocabulary and build a view, and thus a layer, for each taxonomy term. This will lead to having 20 or more views queries and layers if I'd like to display an overview map with 20 or more types of markers. How is this to be judged on the performance side?

Thanks a lot in advance for your help.

SkyWombat