Sometimes I get a few second delay in the forums but the game itself and the UI seems to run fine for me. It was lagging a couple of weeks ago but since then only in the forums.
Im on computer and use Opera for a browser. It had an update back when MFN first got slow and it reset my browser settings. I don't know if that helped or not as I was having a problem with something else and didn't think of checking on MFN. I know it's 1 MFNers demerrit for that.
Not sure if this helps anyone but thought I'd better put it out here just in case.