maybe but not all of them are a waste of memory...
a lot of firefox extensions help me a lot!
adblock plus: just NO ADS!
spanish dictionary: well I need it a lot.
english dictionary: just 4 this web.
dictionary swicher: I need it because I have 2 dictionaries installed.
fasterfox: load some web elements like images faster.
fireftp: my ftp application!
fission: ok I don't really need it.
flashgot: I need it if I want to download with flashget.
gmail manager: I read my e-mails faster.
ie tab: I never open the IE (if I need a web preview for example) because that thing.
image zoom: sure useless in firefox 3.
megaupload sx: Megaupload don't let me download without it.
pageplaylist: just for fun.
proxysel: I'm uninstalling it
speed dial: Better than the bookmarks.
status-bar calculator: Faster than go to start, all programs, accessories, calculator.
stop-or-reload button: I don't really need it.
tab effect: this is a memory leaking bloat like you say but i can't stay without that *** effect!
tab scope: Better than press ctrl+tab repeatedly =P
tempomail: An anti-spam shield.
user agent swicher: well usless but necesary (?)
Your extension is way too much!
unless your machine RAM and processor is too great to support..
FF extension is sure a helpful tool,
like fasterfox, DownThemAll, Reloadbutton, Foxlingo, YahooMailNotifier, AdBlock, and FLVVideoDownload