Hi Patrick, yay out of beta!
In version 1x, there was a limit on the number of places in a tab imposed because each numbered marker was a separate icon and we only provided these up to that number. In version 2 there's not a limit because we generate the numbered markers on the fly. However, we'd still recommend not having more than 200 places per tab in order to keep your load speed fairly good and to avoid cluttering the map and overwhelming your readers. If possible, divide your places up into more tabs, and avoid the temptation to have an "All' tab that shows everything. Remember that the thumbnails in a tab get loaded when your readers visit that tab (or in the case of the first tab, when they load your Shortlist). In Shortlists that reference their images directly via URLs, some authors are pointing at thumbnail images that are too large. If you are making your own thumbnail images (as opposed to uploading images or accessing existing pics in Flickr in which case Shortlist optimizes the thumbnails for you) your thumbs should ideally not be too much larger than 50K.
Hope that helps.
Rupert
