Smartphone vs. Blackberry

I was reading the post on Smartphones vs PDA and I was wondering what the Blackberry would be. Im considering getting one of the three.(PDA, Blackberry, Smartphone) But I am very unsure. I have read up on the latest and greatest but I dont see much difference except for price and name. I have read up on the Samsung Series of PDA's and Smartphones and various other companys such as HP, DELL, and the Palm. I also read up on the Blackberry which I find very interesting. I work at a Law Firm as a Legal Assitant and I attend College. I dont make a lot of cash but I make a decent amount. Can anyone give me there opinion, experience or suggestions?