I've never had a TPK, so I've never had to wrestle with this issue. But my approach would be certainly to see what the group wants to do. If they want to roll up new characters, fine. If not, then I can bring them back.
For me, the issue already sort of exists in my campaign. I don't allow raise dead or resurrection, thus leaving only miracle and wish as a way to bring a character back. But these don't grow on trees (especially in a world like mine where magic is less common than in FR). My preferred method is through role-playing, either on the part of other party members (obviously not possible for a TPK, of course) or on the part of the dead person(s).
As an example, I had one character who died. He awoke then on some non-descript plane with about 100 other people, all looking around puzzled. They were basically told that following the path would bring them to an item that would bring one person back to life. Then, before they could start fighting amongst themselves, two red dragons showed up and the player and npc's wisely started running. Those who survived had a host of other obstacles to overcome. In the end, it was down to two people, the player and an npc - a younger girl who was no adventurer but ran fast (and thus survived). But only one of them could use the item. The player then struck her down and used it himself, although he felt very bad about doing so. Then I really made him feel guilty when an solar appeared and informed him that the entire thing was a contest between himself and a pit fiend, to see if people were basically selfish. Thanks to his action, the pit fiend had won the bet, which gave the devils the right to invade the prime material plane.
This is the sort of thing I like to do, find a way to bring players back that will be enjoyable and - if I am lucky - will make their future lives as adventurers difficult.

To simply have players run off to a cleric, pay their gold and get them raised, just seems so anti-climactic to me. The opposite, just making them roll up another character, basically says don't get too attached to the character and reinforces the notion that what one is playing is a set of stats, not a character IMO. Death to me is a big issue (it happens relatively rarely in my campaigns) and shouldn't be gotten around like some little annoyance. ("Darn, my character died again. Oh well, no biggie, just roll another.")
In my most recent campaign (started about a year and a half ago), I generally have not been able to do this (and have ironically had the biggest problem with player deaths). I have actually added a house rule that allows players to "avoid" death (i.e., the last blow of a monster that would have killed them just instead takes them down to -9 HP, stabilized of course), but at a cost like raise dead (i.e., lose a level). There are several reasons for this, but a large part is that I don't have time for the solo adventures that a character's death typically required. But for a TPK, this wouldn't be an issue - it just replaces the next session.
As to open rolling, I'm definately in the "not" camp. Not only does it allow me to fudge (both for and against the party), but it seems necessary for some things, specifically those rolls that I make for players (e.g., detecting/disarming traps, knowledge rolls, etc.). I mean, they don't always know if they are successful. Did they not find a trap because there isn't one there or because they rolled low?
Just my $.02 worth