I'm having exactly the same problem. I've upgraded to the new beta version of Limewire and that's no better. TBH, this happened a while back just as my 6 months of free updates ended (coincidence?). I paid the tenner again and the download speeds immediately shot back up to 234 kb/s.

I've only recently done this so have no clue why it's so slow. It can't be capped by the ISP as I can download at normal speeds using the internet and other download programs.

Anyone got any thoughts?