I am 51 now all my talent points spent to shadow, for leveling and farming easily ofc. But started to take many "u holy spec?" whispers and when i reply, saying i am an shadow spec they simply do not take me to party. Now this started to create a problem, is it time to change holy because ppl want to see holy if it is not SM you're about to going ? Ppl say after patch holy can grind/farm easy too but when i look talents they don't seem good enough like shadow. What must i do now ? Really need your suggestions, thanks.

If you enjoy Shadow, stay Shadow.  Yes, you will have a harder time getting into instances, just like any DPS, particularly since people will tend to see a priest and assume Holy (just like they see a Warrior and assume Protection).  It will make your life tougher if you're pugging but, as a holy priest, I love running with a Shadow Priest.  You're better off lookin' into a guild to find runs.

Seriously, Shadow Priests are viable for high-end content, so if it's how you like to play, don't switch to a spec you enjoy less.

I totally aggree with IZBadAz.
When you like playing shadow, just do it. Since you have problems getting into groups / instances, focus on that: try to group with some buddies or so. Or join a guild: that will also provide the possibilities to play wiht people who know each other.

And yes: if they like and know you, you will get invited again.

if u like being a bad ass SP but cant get into groups just repsec holy. then mass run instacnes or w/e. then repsec to SP.

what im saying is that wen u repsec to holy stick with it for a while. mass run things b4 u repsec to being a SP. this way ull use less muney repsecing and ull have sum good stuff from instacne or w/e. then again wat do i know my main is a 36

omfg the guy above me posted funniest thing ever.

"but then again what do i know my main is 36"
lol

you dont really need to be a high level to be able to play good
bro.

but ya to answer the thread question.
Just Play the spec you have most fun with.
its not about what other people think.
why play a class or spec when you dont enjoy it or enjoy less of it.

your choice