I don't know if you know about this one, but there is a free online service (you just have to put a link pointing back to their site on one of your sites) it's called OnlyWire, and I have found it very useful.
With that you can Bookmark about 30 sites a couple of them fails but they update often so the most of them are fixed, some of them you have to Finalize, but that's easy as some of them you just put in the captcha in a pop-up, and others you get redirected to the Bookmark site, with most of the fields pre-filled.
When you have the bookmark or addon installed you just choose to Bookmark With or Without Frames (Frames=you can see half of the site you Bookmark) then it pre-fill the Title and the Link, you can then either choose to view the source code of your site and use the Keywords and Description from there, or write new ones for yourself.
Then press "Bookmark" and it will go and do its work and in about 5 min you can go back and finalize the last 5-10 sites which is quickly done.
http://www.onlywire.com/
Hope this can help someone.
KC
This is the sites it Bookmarks to And 3 New was added today which is not shown on my "Submitted Content List" but two of them succeeded in my test.
Ask
Bebo
Bibsonomy
Blinklist
BookmarkSync
Connotea
Delicious
Digg
Diigo
Facebook
Fark
Faves
FriendFeed
Google Bookmarks
Hi5 --------------NEW SUCCEEDED
Jumptags
LinkaGoGo ---------NEW FAILED
Mister Wong
Mixx
Multiply
MySpace
Newsvine
Plaxo
Plurk -----------NEW SUCCEEDED
Propeller
Reddit
Simpy
Slashdot
Spurl
Stumbleupon
Tumblr
Twitter
Yahoo Bookmarks
And this is how it looks like 5 min after pressing Bookmark "Submitted Content List" so you can get an idea on how many failes and succed, the FINALIZE = SUCCEED (The 3 new sites are not shown here) Some of the Failures could be me using a wrong username.
"Submitted Content List"
Ask -->>>>>>>>> SUCCESS
Bebo -->>>>>>>> SUCCESS
Bibsonomy -->>>> SUCCESS
Blinklist -->>>>>> SUCCESS
BookmarkSync -->SUCCESS
Connotea -->>>>
FINALIZE
Delicious -->>>>> SUCCESS
Digg -->>>>>>>>>
FINALIZE
Diigo -->>>>>>>>> SUCCESS
Facebook -->>>>>
FAILURE
Faves -->>>>>>>> SUCCESS
FriendFeed -->>>>>
FAILURE
Google Bookmarks-> SUCCESS
Jumptags -->>>>>> SUCCESS
Mister Wong -->>>> SUCCESS
Mixx -->>>>>>>>>>
FINALIZE
Multiply-->>>>>>>> SUCCESS
MySpace -->>>>>>
FAILURE
Newsvine -->>>>>
FAILURE
Plaxo -->>>>>>>>
FAILURE
Propeller -->>>>> SUCCESS
Reddit -->>>>>>>
FINALIZE
Simpy -->>>>>>>
FAILURE
Slashdot -->>>>>
FINALIZE
Spurl -->>>>>>>> SUCCESS
Stumbleupon -->>
FINALIZE
Tumblr -->>>>>>> SUCCESS
Twitter -->>>>>>> SUCCESS
Yahoo Bookmarks-> SUCCESS
PS: A little advice to avoid getting accounts banned on bookmark sites; Don't Bookmark from the same domain to many times in a row, Bookmark some/many other sites between, and of course make sure it ain't Competing sites you Bookmark.