Yes I agree with what everyone has said. I lost (as of yesterday 24.6.09) 10 lb since 15.6.09. I recently took 4 wks off work to completely overhaul my routine. In order to achieve those results I dropped my daily calorie intake to 1500 but trying to burn a minimum of 3000 daily. I run every other day for about 35 mins, and on Tues and Thurs do 'double' sessions at the gym. So for example, on Thursdays I do street dance *loads of fun* for 40 mins, followed by body pump for another 40 mins. I think you basically have to shock your body because it does get used to a reduced calorie intake and increased exercise over time. Sadly, however, since yesterday I have come down with a HORRIBLE cold, which is I sign I may have been pushing myself a little hard.
Anyway, hope some of this helps - good luck! You'll reach your goal in NO time.