Abdominal Question

I avoid crunches like the plague. I do other core work though.

I (in my not a fitness specialist opinion lol) would say that it is definitely good! .... as long as it is part of a complete diet plan. Core strength is really importany, but if crunches are your only form of exercise, then it's not going to be very effective. As long as you are eating right, and burning calories and fat, then building muscle will only help. But if you aren't also burning fat, then crunches may actually make you look bigger.

I avoid crunches like the plague. I do other core work though.

Amen!!! One of the worst exercises you can do IMO.

If you can add 25 a day that's amazing.
I have read that abdominal muscles can be exercised everyday unlike legs or arms.

Everyday, no. Do a variety of ab exercises. Different crunches, side bends, iso-metric holds (planks, palloff press) are all good exercises.

You're going to find plenty of articles that support or go against spinal flexion for ab work, so you have to incorporate what feels right for you. But variety is good and Ab's everyday is unnecessary. Tons of ab work won't give you a 6-pack if your BF% isn't low anyway.

Many non-ab exercises will strengthen your core too. Deadlifts, Squats, lunges, Bent over rows, Barbell Bench Press, Standing Overhead Press, just to name a few.

read this:

http://startingstrength.com/articles/abs_rippetoe.pdf

Yes ^^^, then read this:
http://www.burnthefat.com/get_six_pack_abs_that_POP.html

proper form while running is enough.

Not quite.

It looks like there's arguments on here from people not to do them. Here's a really good article that discusses ab work and flexion in-general; it's more informative on the situation than "no, you'll destroy your back" or "yeah they're fine". A must read,

http://www.t-nation.com/free_online_article/most_recent/to_crunch_or_not_to_crunch

I hurt my back doing something unrelated and am anti-flexion (for the most part, I do some weighted crunches occasionally) and I follow a lot of the exercises from this,

(Different author from the link above)
http://www.t-nation.com/free_online_article/most_recent/iron_core_how_to_build_a_punchproof_body

I'm currently doing P90x, Tony says that abs shouldn't be worked every day...hence Ab Ripper X is only done 3x a week.

I do this and a little weighted stuff one day, so 4x a week

Crunches are an isolation exercise and not the best way to do it. Do bigger movements that incorporate more muscles... deadlifts and squats with a barbell, for example. Those are all you'll ever need to do.

That's not entirely true. Many trainers thought that at one time but found that they actually improve their overall core and their performance in the lifts you mentioned by training ab's. Surprisingly enough, powerlifters that train with Louis Simmons supposedly do ab work every workout.

Edit: Love your Jim Wendler quote! Jim actually talks about ab work in his 5/3/1 Manual