I've had the same problem. What I've started doing is put the tape up, paint and then pull the tape off immediately so it doesn't have a chance to form a "skin". Also, you might want to apply the paint with your brush in a straight downward motion along the tape line.

There is a new tape out called Frog tape. It's green, not blue. (But be careful, there is other green tape out there that is not Frog). We had new slate tile floors put down in our master bed and bath, and I did not want those little telltale splotches from painting the baseboards. I had read on the paint forum about the Frog tape, so I gave it a go. It is expensive, but I would use it again in a heartbeat. I painted completely normally and this time I did not get even ONE teeny little leak-thru when I pulled the tape off. The tape has some kind of a powder chemical on the underside of it, that forms a seal when it gets wet from the paint. It's truly great stuff.
Lynn

Here is a link that might be useful: Frog Tape

What has worked best for us has been pulling the tape so that it doubles back on itself, rather than drawing the tape straight away from the wall so that the tape and wall form a 90 degree angle the way most people do.

Also scoring it with a razor first would eliminate the edge issue. Removing it while still wet is another one.

Or are you talking about the paint bleeding under the tape? If so paint the edge of the tape with the original color let dry and then paint the new paint.

Thanks for the tips! I finished painting the ceiling a little after 7:30 tonight & the tape pulled off quite nicely - Thank you! I also found that if I got the angle just right when I pulled that it came off better.

By 8:30 I had 2 of the airplanes & the zepplin hanging from the ceiling. DH is getting heavy duty hooks for the military helicopter & the huge tin plane tomorrow. DS1 comes back from his grandparents Saturday & I can't wait for him to see his newly decorated room!

Will take pics & post as soon as I 'm done.

If the paint on which you put the tape has not cured for at least several days or was applied on a surface that was not prepared properly (i.e., lightly sanded and possibly primed), the the tape will pull away the paint. All you can do in this case is go back and touch up the surface on which the paint pulled off with an artist brush.

Here is what works for me to get a straight line on trim/wall joints: Apply the painter's tape, then either apply a very thin bead of clear painter's caulk at the joint, wipe off the excess with a damp cloth - you want a very thin layer, let it dry, paint, let dry for 30 mins. or so, then pull off the tape.

On ceiling/wall joints, apply the 2" tape to the ceiling, indenting into the ceiling about 1/8". Wall/ceiling drywall joints are always uneven, so it's impossible to get a straight line by finding the exact 90 degree angle point. Indenting into the ceiling about 1/8" solves that problem. When you paint, the wall color paint will fill that 1/8" space, but you'll never notice it. All you'll see is a straight line. After you've applied the tape, paint a thin layer of the ceiling paint along the edge of the tape and let dry. Paint a 2-3" strip of the the wall paint along the tape edge, being sure not to "glop" a lot of paint at the tape edge. You don't need to remove the tape right away. You might want to leave it on until you roll the whole wall because invariably, if you're like me, the roller overshoots and I get a splotch of paint on the ceiling which I quickly have to wipe off. With the tape still there, you have that margin of safety.

Once the walls are painted, pull the tape off and you should have a real nice straight line.

Another hint for using the Frog tape: Apply it, then moisten the joint edge with a damp cloth. That activates the "glue", creating the bond ahead of time. I found that the Frog tape works well along the side edges of doors/windows/cabinets, but not as well along baseboards. I still like the caulk idea the best along baseboards.