I'm not so sure if the i815e will out perform the BX in the future.
When it was launched the BX did not perform that much better than the LX. Most of the games and benchmarks were running in L2 so the slower memory bus of the LX wasn't bottlenecking anything.
Today if you benchmark a 667EB against a 700E P3 on a BX, the 667EB wipes the floor with the 700E. The 700E may win in a synthetic test like SANDRA or Norton SI, but when you start benching games and real world apps the faster memory bus of the 667EB takes it over the top.
The difference between the evolution from LX to BX and BX to i815 is that we got a 60% faster memory bus going from LX to BX (66 mhz to 100 mhz). BX and Solano both support the same memory speeds. BX was a clear step up the evolutionary ladder from LX. i815 is sort of the duck billed platapus of motherboard evolution. Part BX part i810, integrated graphics and an AGP slot.
The real advantage the i815e has over the BX is AGP 4X, or more importantly the 1/2 AGP divider in the BIOS. Running a video card on an 89 mhz agp bus is the only thing stopping many people from getting a P3 EB for their BX board. You know you're not gonna be able to over clock your EB too much cuz your video card will limit how far you can go.
I think Solano (i815) is just a band aid solution Intel put forth to try to stop VIA from gaining more ground in the chipset market. Maybe a better question would be "do you think VIA's chipsets will outperform the BX in the future".
We do need a 1/2 AGP divider to run at 133MHz and beyond, we don't need AGP 4X this year. I had high hopes for i815 too, but it's obvious that it was a half hearted effort from Intel. I'll stick with my Abit BE6-2 BX board thanks. It takes my P3 700E up to 917 with much stability, and my V5 5500 seems comfortable on a 131 mhz memory bus ( = 87 mhz AGP)
There's always i850 right?