As I get used to my new Forerunner 220, I have been comparing featured between RunKeeper (what I use today for run and bike rides, via my phone) and Garmin Connect. While not a must have (I can get this by exporting my activities from Garmin Connect as a GPX, and then importing them into Runkeeper - which, oddly enough, seems to lose elevation information at some point along the way), I do like that in RunKeeper I can mouse over either the pace or elevation charts, and it automatically puts a pointer on the map as well (i.e. I hit a x:xx pace at this point in the chart, where in my run was that?). On that topic, it would have the reverse be true as well (hover over a point in my route, and also display the elevation/pace information).
First, if you want to export activity from Garmin Connect to RunKeeper, I highly recommend Tapiriik. You can transfer all of your recent workouts in a batch with a single click (for free), or you can pay $2/year for it to happen automatically. It is a big time saver.
Second, if you want to see where you were when your pace was xxx or how fast you were running on yyy street, you can already do that from the activity player. From the activity details page, click the Player tab on the far right. If you click on the graph, the position indicator on the map will update to reflect where you were at that time.
