What's the matter with you guys? Telling people off doesn't help! Are you angry with those posters or with something else? The first reply could have answered all questions and I could have closed/renamed/moved this thread... right away.

Please be friendly to the not so tech-savvy folks coming here and ask (well questions all over again) simple questions. Speaking for myself the search engine of tmo isn't of the lucky kind and the power search does not help sometimes too.

To the OP:

Welcome to TMO, I hope all your questions are answered by now.
We can not convince you to keep the phone but the people here are right! Why did you buy the phone in the first place? I do a lot of research for stuff $500+ before I even think about buying.

You did not get close to maemo.org yet and that was a mistake, the wiki is full of useful information about shortcuts, HowTos and other stuff. The forum is loaded with discussions about issues or new programs on their way to extras repository. What you want to know about N900 and Maemo5 is already written down at maemo.org or nokia.com.

fmms - frals's program for MMS has hit testing last week (compared to iPhone's MMS release this is amazingly fast!) so if you do not want to risk any stability of your device you have to wait a couple of days till it is tested, afaik it is working ok BUT the setup might be tricky at some point so be careful if you want to try out on testing repository.

USER EXPERIENCE MAY CHANGE DURING ONLINE PLAY (be aware that this experience may be extras-testing and extras-devel repositories and that those repositories are able to give you beautiful black brick with touchscreen and keyboard and you make further experience with reflashing your device, means NO FUN for inexperienced users)

If you are new to linux based OSs you may look up any terminology you do not know at wikipedia/google as linux/GNU in its full beauty is documented all over the place (internet).

CLOSED

EDIT: for the playlist thing: long-tap is like right-click to give context menu > for adding files you need to go to any list view not being the player (does only work for radio and audio files), you can add play-lists, folders or single files via context menu > add to current play-list.
The delete from play-list functions is due to some fault turned of in the current PR-Firmware, to turn it on you need to change the gconf entry (I guess you do not know what I am talking about so keep your hands off or search the forum for advice). PR 1.2 will have some more features and different view of the mediaplayer. PR 1.2 adds video calling too (you didn't ask but that's right after MMS on the list).