Where's the stock keyboard's predictive dictionary located?
EDIT: it's not the answer you want, but provides useful info nonetheless, here's the userdict file:  

/data/data/com.android.providers.userdictionary/databases/user_dict.db

You need root to access it and sqlite3 to view the data inside (here's mine):

localhost # cd /data/data/com.android.providers.userdictionary/databases/   
localhost # sqlite3 user_dict.db .dump                                                        
PRAGMA foreign_keys=OFF;
BEGIN TRANSACTION;  
CREATE TABLE android_metadata (locale TEXT);  
INSERT INTO "android_metadata" VALUES('de_DE');  
CREATE TABLE words (_id INTEGER PRIMARY KEY,word TEXT,frequency INTEGER,locale TEXT,appid INTEGER);  
INSERT INTO "words" VALUES(2,'ok',128,'de',0);  
INSERT INTO "words" VALUES(3,'LG',128,'de',0);  
INSERT INTO "words" VALUES(4,'no',128,'de',0);  
COMMIT;