How many gigabytes are the new 'Mummy' blu-rays?

[Darth Lavender]

Just wondering about Universal's re-encoding of their Blu-ray releases.
Reviews seem to say that the image still looks completely identical to the HDDVDs (not necessarily a bad thing, if the HDDVD looked good) but I just read one review which claims the blu-ray (of 'The Mummy') is "over 30 gig"
Can someone tell me how far over 30 gigabytes? I'm wondering if these are actual new encodes, or if the difference in file size is entirely due to the added extras (which would explain the lack of apparent picture improvement)

(Not actually interested in re-buying 'The Mummy' movies myself. First was a quickly regretted impulse buy, and the other two were only bought as part of the HDDVD firesales (regardless of movie quality, it's tough for a new adopter to turn down 2 hours of demo-material for $10 each)