At times this works for me when I have had similar problems: At the command prompt type: ipconfig /flushdns If you are running Windows Vista, right click the command prompt and and select "Run as Administrator" before typing the command.
Haven't really noticed it myself, although I was out for a few hours when most people were commenting on the slowdown. Also, cancuncare is actually hosted in the US so it cant have been a problem connecting to the US per se.
