Keep at it. I changed the date, got the first update through within seconds and that improved performance a LOT. Then about a week later I got the second update to 2.1 and it's so much better, whole phone is transformed although it seems back to its original 'slow-ness'
Thats with Orange and I bought my phone unlocked off eBay.
How are people coping with the battery? Just checked my phone and after turning wireless off and adjusting brightness, screen off timer, etc it's currently at 48 hours up time and still just above half battery life, better than it used to do.