We are having the same problem, the plugins show that there is an update available, we click to update, the process happens and it says that they have updated successfully, but when we go back to the plugins page they still say there is an update available.
When we look at the plugin folders via FTP they show the date we updated the plugin and the files have actually been updated. Something isn't connecting with WordPress somewhere. Any idea what can be done?
We've done a manual WordPress upgrade and that didn't fix anything.