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Just some data to consider based upon your questions and other comments:

Screen type:
MBP - matte or glossy
MB - glossy only

Screen size:
MBP - 15.4 inch
MB - 13.3 inch

Resolution:
MBP - 1440 x 900
MB - 1280 x 800

Weight:
MBP - 5.4 pounds
MB - 5.0 pounds

Cubic Size:
MBP - 135.36 cubic inches
MB - 123.1 cubic inches

Graphics Card:
MBP - NVIDIA GeForce 8600M GT graphics processor with dual-link DVI support; 128MB of GDDR3 SDRAM on 2.2GHz configuration; 256MB of GDDR3 SDRAM on 2.4GHz and 2.6GHz configurations
MB - Intel GMA X3100 graphics processor with 144MB of DDR2 SDRAM shared with main memory

Comments:
- With the MB, there is no option for a matte screen.
- Overall the MBP is not that much bigger than the MB in terms of volume -- Less than 10% bigger.
- The MBP gives you much more screen real estate -- About 26.5% more.
- The MBP gives you dedicated video with separate VRAM instead of sharing main memory.
- The MBP has a regular style keyboard.
- Both weigh about the same.

In some areas, such as weight, there is not much difference between a MBP and a MB. In other areas there is a very significant difference such as screen type or real estate.

The key is to get what you are comfortable with using -- even if you have to wait.
 
I went from a 2 year old Dell 15.4" to a Macbook and found myself going back to the Dell due to missing the nice big screen. It's a totally personal thing however, and I'm selling my MB to a friend in order to upgrade to an MBP. If you think the 13.3" is going to be too small, then you're probably right. I believe the 2.16GHz MBP w/ 1GB of RAM is only $1499 refurb (but you gotta get up early to catch it), that's what I'd go with if you want to buy it now. Given that you don't need it until next summer, I'd just wait until the current Gen 2.2GHz w/ 2GB and the 8600GT drops to that price (likely after the next update) and then buy that... unless you're actually eligible for that 20% discount thechidz mentioned, in which case I'd be all over it, either now or next summer. Another benefit of waiting is they may get the LED screen issues resolved by then.

Edit: btw, I don't have any benchmarks handy, but I'd be shocked if the last gen 2.16 mbp w/ discrete graphics didn't kick the crap out of the current gen x3100 macbook. Could be wrong, but like I said, I'd be shocked... and the current gen w/ 8600 is no contest.
 
I went from a 2 year old Dell 15.4" to a Macbook and found myself going back to the Dell due to missing the nice big screen. It's a totally personal thing however, and I'm selling my MB to a friend in order to upgrade to an MBP. If you think the 13.3" is going to be too small, then you're probably right. I believe the 2.16GHz MBP w/ 1GB of RAM is only $1499 refurb (but you gotta get up early to catch it), that's what I'd go with if you want to buy it now. Given that you don't need it until next summer, I'd just wait until the current Gen 2.2GHz w/ 2GB and the 8600GT drops to that price (likely after the next update) and then buy that... unless you're actually eligible for that 20% discount thechidz mentioned, in which case I'd be all over it, either now or next summer. Another benefit of waiting is they may get the LED screen issues resolved by then.

I agree. I have a MB and just today "upgraded" to a MBP. I personally don't need the power of MBP but I came to a realization that the screen size on my MB was "uncomfortable". Personally I found 15.4" to be the perfect size for me to view and carry around.

Definetely before you buy, compare both MB & MBP screen side by side.
 
Definetely before you buy, compare both MB & MBP screen side by side.
Sage advice.

Also worth noting, is that the MBP 15, has the same pixels as the iMac 17.

Twenty five percent more pixels between the MB and MBP does not sound like much, but in daily use it can make a big difference if you need the screen real estate -- especially while on the go.
 
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