[Xperia Arc General] AdamUpNorth:
Here's Cim_XII's 1st page list but I sorted it and added some comments as best I could. I've also added some additional removals that I've done without any weird side effects.

All my changes are in blue.

Cim_XII, thanks for starting this. Great post. Can you please update the first page.

Anonyous Usage Stats 1.0 (Sends stats to SE)

android.tts (TTS Service 2.3.2)

Chinese Keyboard

com.sonyericsson.androidapp.microblog.apk (Weibo)

com.sonyericsson.digitalclockwidget.apk (Digital Clock 1.0) (small digital clock from X10)

com.sonyericsson.learningclient 1.0.0 (Stock keyboard word learned. Not needed if you use a different keyboard)

com.sonyericsson.widget.digitalclock.apk (Digital Clock 1.11.0) (new larger digital clock)

com.sonyericsson.youku.apk (Youku)

CrashMonitor 1.0 (Sends crash info to SE)

Data traffic 1.0 (turns data on/off. Don't need if you use 3rd part switcher like Extended Controls)

Default Input 3.0 (Stock keyboard)

devicemonitor 1.0 (Not sure about this one but I haven't had any problems with it disabled)

Diagnostic Tool 1.0 (Not sure about this one but I haven't had any problems with it disabled)

email 3.0.0 (stock eMail app. Not needed if you use Gmail)

HDMI (will probably disable the HDMI-functionality!)

Home screen tips 1.0 (Widget that gives you tips about android)

Japanese Keyboard

Let's Golf HD

LiveWare Manager (activates programs when earphone/usb/bluetooth devices are attached.)

Magic Smoke Wallpapers 2.3.2

Media server (Allows you to share your media with other wireless devices. aka DLNA.)

Media shortcuts 1.0 (stock widget that lets you start the gallery or music player)

Music Visualization Wallpapers 2.3.2 (includes 4 live wallpapers "Spectrum, VU meter, waveform and Many")

News & Weather

Office Suite

OMA Client Provisioning 1.0.0 (Not sure about this one but I haven't had any problems with it disabled)

Play Now

POBox Touch 4.0 (Apparently has something to do with Chinese keyboard)

Postcard (Postcard app that lets you send a postcard electronically)

QC SEMC Service 1.0.0 (As far as I can tell, SE monitoring junk)

Retail Demo 2.4.0 (Don't know function but it sounds like junk. Removed and no side effects seen)

Setup guide

Sony Ericsson Home 1.0 (Stock launcher. Not needed if you use other launcher. i.e. Launcher Pro, ADW, etc...)

Sony Ericsson Sync (Sync your contacts to Sony's servers. Not needed if you use Google's sync)

Sony Ericsson Sync client wizard

Support & Setup Guide (Electronic users guide)

Track ID (Identify songs. Can alternately use Shazam from the market)

Whatsapp messenger

Widgets On/Off 1.11.0 (can be removed if you use other powercontrollers, like extended/widgetsoid etc.)

Timescape related

com.sonyericsson.androidapp.timescapefeedsplugin

EventStream

EventStreamPluginCallLog

EventStreamPluginFacebook

EventStreamPluginFoursquare*

EventStreamPluginShowNearby*

EventStreamPluginTelephony

EventStreamPluginTwitter (com.sonyericsson.eventstream.twitterplugin.apk)

Extension Search (searches the market for more Timescape extensions)

Kaixin plugin for Timescape

Spotify extension for timescape

TimeScapeSpline

TimeScapeWidget

Twitter extension for timescape

Updated 05/12/11 (11:29pm EST): Added Data traffic 1.0, Magic Smoke Wallpapers, Media shortcuts