well my stories don't sound as extreme as urist's fort, but in my last fort i got reminded pretty adly that now some enemies can climb. it was still pretty early in my fort, didn't had every room fully build yet and no hospital or barracks yet, as a goblin siege came. i had ne inner bridge (within the entrance tunnel) but a complete outer wall with bridge, i raised the bridge quickly and thought that i was safe...wrong....a bowman climbed down from the cliffside and murdered everyone.....it was hilarious because he still had the pre 40.10 projectile speed bug, it looked like the shots came from a machinegun.
i also love my current fort, good geographics, good amount of iron ore (no flux yet), a mostly quiet cavern directly below (only 10 floors below) and i got the usual three lvl 3 x weapon profession dwarf and a maceman (also migrant) with lvl 10 mace, lvl 10 doger and lvl 10 discipline (also 1-2 armor but hey, high dodging and deadly with mace). currently a forgotten beast appeared which seemed to spill some liquid. it was at first pretty hilarious because in the cave was a troll i didn't dare to fight yet the forgotten beast landed directly next to him. both were in 7 deep water and duo to the liquid it seams the water where the forgotten beast stood were freezing constantly. i though "hey, maybe it will stuck there being freezed till i am sure i can kill it.". it eventually killed the troll and made his way towards my fort. it was still in the stairways leading up to my main fortress when i send my high-lvl macedwarf to give the beast a welcoming party. i also send the three other "normal" militia-dwarves but either they weren't there in time or had run in fear, idk, they weren't there. the macedwarf got 1-2 good hits on the forgottenbeast, damaging two of the beasts bodyparts (i think one arm and one leg), but then the beast started bashing (fists) and kicking, it threw the dwarf 2-3 times away and smashed one of his arms (i didn't know which one exactly, i think it was even the weapon-hand) .... i didn't read in the combat log that he died (found dead or gave in to pain or any other fatal wound), but he suddenly vanished from my squad screen so i assume that he is a goner. the forgotten beast is now on its way to my fort, he already killed the high-level macedwarf mere seconds and now the only thing that stands between him and my fort are three weaponlevel 3, otherwise untrained militia-dwarves and i have no hope of surviving this. .... and i loved this fort, it went so well like never before T.T. .... until now.
edit: my facepalm moment is that recently i can't seem to get a working / fully-featured fort started, make no mistake i am still quite new to the game, but with DF2012 i constantly got to a lategame fort. maybe because i also got no real sieges in my previous forts (DF2012), duo to bug or otherwise, just some snatchers and small ambushes but never sieges. now i rarely get snatchers but sieges still in the first year x'D.....it is "FUN".
Edit2: now i remember something very hilarious, in my current fort i got a pretty long goblin siege recently, FUN part was that one of the goblin was a werecat. it transformed and killed 3 of his brothers and infected another goblin with the disease. so in the end the werecats / the goblin themselve took care of each other x'D. pre 40.10 was also funny with the buggy / untweaked morale system that when i embarked near goblins and towers that sometimes i got both siegers and one runs in fear of the other. or sieges end prematurely because the enemy sees too much corpses (animals or older attackers). was quite hilarious
.