Hey KEMNAYCHRIS,
Apparently yes , according to the garage there is (some) water in the drivers footwell, alas the footwell has about 1" of carpet+sound denting material so you really need lots to see it.. If you have lots then from my research there are two possible causes
1. The scuttle/Plenumcover drains, the cavity beneath the windscreen wipers is blocked. Apparently there are some drains here, if they get blocked then they over fill into the cabin.. Also check your pollen filter (passenger side on mk5) if its soaked then this might be it..
See
http://i252.photobucket.com/albums/hh5/john_s3/Plenumcover.jpg for how to remove/check the cavity
2. Windscreen is leaking... Did you have it replaced recently???
Apparently the only way to check this is to remove the entire dash and put a hosepipe against the car, or remove the windscreen and do what I did..
Considering the bill I was facing was already at the £500mark (£150diagnostic+parts+labour) Id say its something you want to look at..
As E30DOM said its a fantastic Christmas present... , and a big sigh of relief, not only because I dont have to pay for it, but mainly because we now KNOW where the water was coming in... it would have been worse if it wasnt the windscreen, if it was then we still wouldnt know where the water was coming in from..