Most notebooks have all the basic ports, one that you should have to help with future peripherals is a USB port . Most notebooks have video out but only a few have video in. Make sure that the lid covering your ports are sturdy if you will be accessing them a lot, many complaints of having these snap off the first month or so. Micron XPE and Dell LM have the nicest layout, covers swing open AND have sliding cover. 56k or higher, also try and get the low-power cards as it will help with battery life.
Most notebooks have ports to plug in an extenal monitor and keyboard.
The Replicator is just an easy way to connect your notebook to the external monitor, keyboard, mouse, modem, speaker, etc. without having to plug and unplug 57 cords. If you are looking to buy now but want to keep waiting until the prices drop or newer technology comes out, just buy now. I used to think that you could get away with saving a little money and going with a non-brand name. But after all the e-mails I've received from owners who no longer have a company to provide support for their notebook, I've realized that you would be better off spending a little more and getting a brand name.