Ports and remakes aren't necessarily a bad thing.
It gives a chance to those that hadn't played the game before a second chance (on a different system).
Remakes, on the other hand, usually have graphical upgrades and more or less some additional content and tweaks to make the game easier (yes, games used to be challenging).

It allows the devs to push out more games in shorter time than a brand new game.

The only thing I object about this is the price. It should be cheaper than the regular brand new games, such as RE4Wii.

Ports and remakes are only bad if they're done poorly. Ninja Gaiden Sigma and Resident Evil 4 Wii were excellent improved ports.

When people stop buying em.

Ports between 360 and PS3 are never going to end, it just makes good business sense.  It's not that different from last generation - the only difference is a few PS3 exclusives were ported to 360 after publishers realized it wasn't so popular after all.  PS2/PSP/Wii ports are also here to stay, but PS2 will be phased out over time...probably all but gone by Christmas 2008.

Old games getting remade on new systems?  I think we'll continue to see these on Wii into next year, because a lot of publishers are trying to play catch-up on the system.  Again, I'd say they'll be pretty much gone by the end of 2008.  I don't think it's that much of an issue on PS3 and 360...you've got Ninja Gaiden Sigma and Bully, and there were a few more at the Xbox 360 launch, but it's not that common.

Ninja Gaiden Sigma is a remake, it's not a port. When a game receives new bosses, levels, character, overhauled graphics, it's a remake not a port.

The only ports/remakes I get tired of are ones that are completely overplayed.

Perfect example: Final Fantasy.

Its history is as follows:

Final Fantasy (Famicom - 1987)
Final Fantasy (MSX2 - 1989) Sidenote: A Sony-and-Microsoft console.
Final Fantasy (NES - 1990)
Final Fantasy I•II (Famicom - 1994) Sidenote: The last Square game on Famicom.
Final Fantasy (WonderSwan Color - 2000)
Final Fantasy (PlayStation - 2002)
Final Fantasy I & II Premium Package (PlayStation - 2002) Sidenote: Yes, they released separated and combined versions in the same year.
Final Fantasy Origins (PlayStation - 2003)
Final Fantasy I & II: Dawn of Souls (GBA - 2004)
Final Fantasy (Mobile Phone - 2004)
Final Fantasy (PSP - 2007)

Over the course of 20 years, it has been released a total of 11 times.

If you're a company (like Capcom) and you can spend somewhere between $100,000 and $5,000,000 to port a game (potentially with some new content or upgrades) to a platform and sell 500,000 copies wouldn't you do it? You'd be looking at a profit of $5,000,000 to $15,000,000 which could be used to offset current development costs.

Certain games (like Okami) often sell far worse mainly because they're released on the wrong platform, at the wrong time, or against tough competition. A publisher can take a game like this and produce an upgraded port to another system in the hopes of recovering lost money and potentially building a franchise.

Still,this generation is seeing A LOT more ports/remakes than the previous ones did...and Soriku,many 'main games' are already headed for PS3/360....GTA4,Devil May Cry 4,Metal Gear Solid 4,FFXIII,Resident Evil 5,Silent Hill 5,Soul Calibur 4,etc.

I don't think it is called a "port" if it is released on the 360/PS3. It is a called a "multi-platform" game.

How are multiplatform games bad? It gets the developers a better shot at selling more titles and making the money necessary to make more games.