Well, what to expect kinda depends on when you go! If you're going before April, expect a number of attractions to be closed because of refurbishment. Of course, Space Mountain will be closed until sometime next year, as most of Tomorrowland seems to be. Also, Disneyland is much more of a locals park than WDW, so expect more in the way of afternoon crowds, as people head to the park after work/school, and weekends are usually fairly busy.
Indiana Jones over in Adventureland is definitely not to be missed! This is another one that closed until April for refurb (this is its first major refurb since opening in 95). I think that the Haunted Mansion and Splash Mountain are just about on par with WDW. Pirates, though, is much, much, much better at Disneyland than it is at WDW! Highly reccommended. Big Thunder Mountain is about the same as WDW. Some of the stuff DL has that WDW does not that I think is not to be missed: (aside from Indy) Storybookland Canal Boats, Mr. Toad (still here, still great!
), Roger Rabbit's Cartoon Spin, the Matterhorn (of course!), Great Moments With Mr. Lincoln. As for Fantasmic - waaaaay better at Disneyland! Don't miss that one! Parade of the Stars is a bit disappointing, but it is fun if you get picked to be one of the guest performers.
If you're going over to California Adventure as well, I reccommend doing this only if you have a park hopper. As much as I've come to love it, it's just not worth paying a full day's price for it. California Screamin' and Soarin' Over California are not to be missed! MuppetVision 3d and WWTBAM Play It are the same as at WDW. Aladdin: A Musical Spectacular is wonderful!! (notice me avatar
) Also, weekends at night they run "Disney's Electrical Parade," which is basically MSEP with a name change.
-Kirsten