Clothing:... How quickly did everyone find a tailor? (I'm sort of excited that I can get things tailored easily.)
Shoes: ... Two of the pairs are broken; should I get them cobbled beforehand or in China?
Lots of both shoes available, generally cheaper than in the West. Tailoring and shoe repair much cheaper here.
Toilet paper: No one's really mentioned this, yet I've heard it from all of my family and friends. Should I bring massive quantities of toilet paper?
Do not bring it; it is available in every supermarket. Do carry some in your purse once you are here; public toilets here almost never provide it.
Phone: International smart phone before China? Buy a separate phone for communication within China?
If you already have a GSM phone with 900/1800 MHz frequencies used here (& Europe, Australia, Africa, rest of Asia, ...), bring it. You can just buy a SIM card here & away you go. The frequencies used in N & S America, 850 & 1900, will not work here, so the typical US or Canadian GSM phone will be useless.
More at: http://wikitravel.org/en/China#Telephone
I have a million-pound PS3. Should I bring it or leave it?
Does it run on 220 volts, the standard current here? Can you bring just the box, buy a monitor here?
For this,or other heavy stuff like books, it is worth checking whether mailing it to yourself will be cheaper than paying excess baggage fees.