I've been having a go at this over the last couple of days. My rough cut of the first film comes in at 103 minutes (without credits). That's mostly been chopping whole scenes, although a number of times I've had to make fiddlier snips. That's just a first pass, though; I've been as generous as I can, with a view to cutting more later. I'll watch it through to see how the pacing goes, and try to shave off another half hour or so if I can.

Changes so far (that I can remember):

Prologue completely gone (might use prologue from part 2 as a prologue; we need something to precede "good morning")
Unexpected Party trimmed
Troll scene trimmed for childishness
Radagast severely trimmed (He shows up, quick flashback to Dol Guldur, then he dashes off; the extended chase scene is cut)
No flashbacks to battle with Azog
Rivendell trimmed; no White Council
Stone giants completely gone and not missed
Stupid CGI in Goblin-town gone; Great Goblin trimmed.
Gollum introduction edited because as it stands it assumes the audience knows him; I want to introduce him more gradually and make him creepier for the audience who hasn't seen LOTR. This will need more work for continuity and pacing.
Goblin chase almost completely gone — they start to run, it cuts back to Bilbo, next we see is the escape from the mountain. No stupid CGI.
Azog completely cut until the pine-tree battle, and then cut down to be just another Orc. Thorin gets left behind or thrown out of his tree — we don't see — and they only realise when not!Azog's warg attacks him.

I may cut down Thorin's mistrusting-Bilbo arc, which was quite exaggerated from the book, in which case I can cut down the last battle even more, eliminate Azog, and lose a minute or two elsewhere.

I haven't actually seen the second film yet, so I'm not sure what I'll be able to do with it, but at the very least I'll try to eliminate Legolas and Tauriel and Smaug's golden shower.