I bought 2Xtreme last night and stayed up playing till about 2am.
Here are my opinions:

First of all the game overall is great I had a lot of fun and did not
want to go to bed. However, here are a few things that hold the game
back or are great improvements!

1. Tricks are a great idea but hopefully there will be more than the 4
standard ones. This is the best feature of the game...if is fun just
to see if you can pull of more than 1 or 2 in the same jump. Also if
you are in the lead and you get bored, just do a trick...you get
points...more point for a more button combination tricks. However,
don't do them too late. If you are in the middle of a move and don't
have time to complete it, you WIPEOUT!

2. Not being able to select the vehicle you ride on is kind of a drag
(of course there would be no option on the snow courses)

3. The graphics are a bit grainy compared to the first one.

4. There are really only 4 courses, Los Angesles-Skate board, Africa -
Bike, Japan - Snowboard, and Las Vegas - Rollerblades. Each city has 3
different tracks (which all look almost identical) making a total of
12 tracks.

5. There is no street luge  :~(   which was my favorite vehicle.

6. You can only punch or kick....not both...like on rollerblades and
the skateboard you can only punch not both punch and kick.

7. Player movement is much more realistic and smooth.

8. No more comentator...she was stupid anyway and took way too long to
load.

9. Money is of no use...u can't buy better vehicles...bummer

10. They now have power up gates...Ready to rumble (stronger
fighting), Power jump (jump higher), Heath (Instant health), Speed
(makes you go faster.

11. You also get points for knocking people down.

Well, that is just my first impressions. I really like this game and
will keep it. Even though there are a few things wrong with it, it is
still an awesome game and fun to play...especially in classic 2 player
split screen!